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Author | Beckers, A.; Thewissen, M.; Sorée, B. | ||||
Title | Energy filtering in silicon nanowires and nanosheets using a geometric superlattice and its use for steep-slope transistors | Type | A1 Journal article | ||
Year | 2018 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 124 | Issue | 14 | Pages | 144304 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | This paper investigates energy filtering in silicon nanowires and nanosheets by resonant electron tunneling through a geometric superlattice. A geometric superlattice is any kind of periodic geometric feature along the transport direction of the nanowire or nanosheet. Multivalley quantum-transport simulations are used to demonstrate the manifestation of minibands and minibandgaps in the transmission spectra of such a superlattice. We find that the presence of different valleys in the conduction band of silicon favors a nanowire with a rectangular cross section for effective energy filtering. The obtained energy filter can consequently be used in the source extension of a field-effect transistor to prevent high-energy electrons from contributing to the leakage current. Self-consistent Schrodinger-Poisson simulations in the ballistic limit show minimum subthreshold swings of 6 mV/decade for geometric superlattices with indentations. The obtained theoretical performance metrics for the simulated devices are compared with conventional III-V superlatticeFETs and TunnelFETs. The adaptation of the quantum transmitting boundary method to the finite-element simulation of 3-D structures with anisotropic effective mass is presented in Appendixes A and B. Our results bare relevance in the search for steep-slope transistor alternatives which are compatible with the silicon industry and can overcome the power-consumption bottleneck inherent to standard CMOS technologies. Published by AIP Publishing. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000447148100011 | Publication Date | 2018-10-11 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 3 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 2.068 | ||
Call Number | UA @ lucian @ c:irua:154729UA @ admin @ c:irua:154729 | Serial | 5099 | ||
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Author | Mohammed, M.; Verhulst, A.S.; Verreck, D.; Van de Put, M.L.; Magnus, W.; Sorée, B.; Groeseneken, G. | ||||
Title | Phonon-assisted tunneling in direct-bandgap semiconductors | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 125 | Issue | 1 | Pages | 015701 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | In tunnel field-effect transistors, trap-assisted tunneling (TAT) is one of the probable causes for degraded subthreshold swing. The accurate quantum-mechanical (QM) assessment of TAT currents also requires a QM treatment of phonon-assisted tunneling (PAT) currents. Therefore, we present a multi-band PAT current formalism within the framework of the quantum transmitting boundary method. An envelope function approximation is used to construct the electron-phonon coupling terms corresponding to local Frohlich-based phonon-assisted inter-band tunneling in direct-bandgap III-V semiconductors. The PAT current density is studied in up to 100 nm long and 20 nm wide p-n diodes with the 2- and 15-band material description of our formalism. We observe an inefficient electron-phonon coupling across the tunneling junction. We further demonstrate the dependence of PAT currents on the device length, for our non-self-consistent formalism which neglects changes in the electron distribution function caused by the electron-phonon coupling. Finally, we discuss the differences in doping dependence between direct band-to-band tunneling and PAT current. Published under license by AIP Publishing. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000455350200021 | Publication Date | 2019-01-02 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 2 | Open Access | |
Notes | ; This work was supported by Imec's Industrial Affiliation Program. ; | Approved | Most recent IF: 2.068 | ||
Call Number | UA @ admin @ c:irua:156735 | Serial | 5224 | ||
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Author | Verreck, D.; Verhulst, A.S.; Van de Put, M.L.; Sorée, B.; Magnus, W.; Collaert, N.; Mocuta, A.; Groeseneken, G. | ||||
Title | Self-consistent procedure including envelope function normalization for full-zone Schrodinger-Poisson problems with transmitting boundary conditions | Type | A1 Journal article | ||
Year | 2018 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 124 | Issue | 20 | Pages | 204501 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | In the quantum mechanical simulation of exploratory semiconductor devices, continuum methods based on a k.p/envelope function model have the potential to significantly reduce the computational burden compared to prevalent atomistic methods. However, full-zone k.p/envelope function simulation approaches are scarce and existing implementations are not self-consistent with the calculation of the electrostatic potential due to the lack of a stable procedure and a proper normalization of the multi-band envelope functions. Here, we therefore present a self-consistent procedure based on a full-zone spectral k.p/envelope function band structure model. First, we develop a proper normalization for the multi-band envelope functions in the presence of transmitting boundary conditions. This enables the calculation of the free carrier densities. Next, we construct a procedure to obtain self-consistency of the carrier densities with the electrostatic potential. This procedure is stabilized with an adaptive scheme that relies on the solution of Poisson's equation in the Gummel form, combined with successive underrelaxation. Finally, we apply our procedure to homostructure In0.53Ga0.47As tunnel field-effect transistors (TFETs) and staggered heterostructure GaAs0.5Sb0.5/In0.53Ga0.47As TFETs and show the importance of self-consistency on the device predictions for scaled dimensions. Published by AIP Publishing. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000451743900015 | Publication Date | 2018-11-30 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 1 | Open Access | |
Notes | ; This work was supported by imec's Industrial Affiliation Program. ; | Approved | Most recent IF: 2.068 | ||
Call Number | UA @ admin @ c:irua:156291 | Serial | 5228 | ||
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Author | Milovanović, S.P.; Covaci, L.; Peeters, F.M. | ||||
Title | Strain fields in graphene induced by nanopillar mesh | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 125 | Issue | 8 | Pages | 082534 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The mechanical and electronic properties of a graphene membrane placed on top of a triangular superlattice of nanopillars are investigated. We use molecular dynamics simulations to access the deformation fields and the tight-binding approaches to calculate the electronic properties. Ripples form in the graphene layer that span across the unit cell, connecting neighboring pillars, in agreement with recent experiments. We find that the resulting pseudo-magnetic field (PMF) varies strongly across the unit cell. We investigate the dependence of PMF on unit cell boundary conditions, height of the pillars, and the strength of the van der Waals interaction between graphene and the substrate. We find direct correspondence with typical experiments on pillars, showing intrinsic “slack” in the graphene membrane. PMF values are confirmed by the local density of states calculations performed at different positions of the unit cell showing pseudo-Landau levels with varying spacings. Our findings regarding the relaxed membrane configuration and the induced strains are transferable to other flexible 2D membranes. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000460033800038 | Publication Date | 2019-01-16 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 9 | Open Access | |
Notes | ; S.P.M. is supported by the Flemish Science Foundation (FWO). ; | Approved | Most recent IF: 2.068 | ||
Call Number | UA @ admin @ c:irua:158605 | Serial | 5231 | ||
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Author | Chen, Q.; Li, L.L.; Peeters, F.M. | ||||
Title | Inner and outer ring states of MoS2 quantum rings : energy spectrum, charge and spin currents | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 125 | Issue | 24 | Pages | 244303 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We investigate the energy levels and persistent currents of MoS2 quantum rings having different shapes and edge types in the presence of a perpendicular magnetic field by means of the tight-binding approach. We find states localized at the inner and outer boundaries of the ring. These energy levels exhibit different magnetic field dependences for the inner and outer ring states due to their different localization properties. They both exhibit the usual Aharanov-Bohm oscillations but with different oscillation periods. In the presence of spin-orbit coupling, we show distinct spin and charge persistent currents for inner and outer ring states. We find well-defined spin currents with negligibly small charge currents. This is because the local currents of spin-up and -down states flow in opposite directions. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000474439600026 | Publication Date | 2019-06-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 11 | Open Access | |
Notes | ; This work was supported by the Hunan Provincial Natural Science Foundation of China (Nos. 2015JJ2040, 2018JJ2080, and 2018JJ4047), the National Natural Science Foundation of China (NNSFC) (No. 51502087), the Scientific Research Fund of Hunan Provincial Education Department (Nos. 15A042, 15B056, and 17B060), and the Flemish Science Foundation (FWO-VI). ; | Approved | Most recent IF: 2.068 | ||
Call Number | UA @ admin @ c:irua:161309 | Serial | 5417 | ||
Permanent link to this record | |||||
Author | Bafekry, A.; Shayesteh, S.F.; Ghergherehchi, M.; Peeters, F.M. | ||||
Title | Tuning the bandgap and introducing magnetism into monolayer BC3 by strain/defect engineering and adatom/molecule adsorption | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 126 | Issue | 14 | Pages | 144304 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Using first-principles calculations, we study the structural, electronic, and optical properties of pristine BC3. Our results show that BC3 is a semiconductor which can be useful in optoelectronic device applications. Furthermore, we found that the electronic properties of BC3 can be modified by strain and the type of edge states. With increasing thickness, the indirect bandgap decreases from 0.7 eV (monolayer) to 0.27 eV (bulk). Upon uniaxial tensile strain along the armchair and zigzag directions, the bandgap slightly decreases, and with increasing uniaxial strain, the bandgap decreases, and when reaching -8%, a semiconductor-to-metal transition occurs. By contrast, under biaxial strain, the bandgap increases to 1.2 eV in +8% and decreases to zero in -8%. BC3 nanoribbons with different widths exhibit magnetism at the zigzag edges, while, at the armchair edges, they become semiconductor, and the bandgap is in the range of 1.0-1.2 eV. Moreover, we systematically investigated the effects of adatoms/molecule adsorption and defects on the structural, electronic, and magnetic properties of BC3. The adsorption of various adatoms and molecules as well as topological defects (vacancies and Stone-Wales defects) can modify the electronic properties. Using these methods, one can tune BC3 into a metal, half-metal, ferromagnetic-metal, and dilute-magnetic semiconductor or preserve its semiconducting character. Published under license by AIP Publishing. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000503995300019 | Publication Date | 2019-10-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 56 | Open Access | |
Notes | Approved | Most recent IF: 2.068 | |||
Call Number | UA @ admin @ c:irua:165160 | Serial | 6328 | ||
Permanent link to this record | |||||
Author | Bafekry, A.; Shayesteh, S.F.; Peeters, F.M. | ||||
Title | Two-dimensional carbon nitride (2DCN) nanosheets : tuning of novel electronic and magnetic properties by hydrogenation, atom substitution and defect engineering | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 126 | Issue | 21 | Pages | 215104 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | By employing first-principles calculations within the framework of density functional theory, we investigated the structural, electronic, and magnetic properties of graphene and various two-dimensional carbon-nitride (2DNC) nanosheets. The different 2DCN gives rise to diverse electronic properties such as metals (C3N2), semimetals (C4N and C9N4), half-metals (C4N3), ferromagnetic-metals (C9N7), semiconductors (C2N, C3N, C3N4, C6N6, and C6N8), spin-glass semiconductors (C10N9 and C14N12), and insulators (C2N2). Furthermore, the effects of adsorption and substitution of hydrogen atoms as well as N-vacancy defects on the electronic and magnetic properties are systematically studied. The introduction of point defects, including N vacancies, interstitial H impurity into graphene and different 2DCN crystals, results in very different band structures. Defect engineering leads to the discovery of potentially exotic properties that make 2DCN interesting for future investigations and emerging technological applications with precisely tailored properties. These properties can be useful for applications in various fields such as catalysis, energy storage, nanoelectronic devices, spintronics, optoelectronics, and nanosensors. Published under license by AIP Publishing. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000504007300023 | Publication Date | 2019-12-02 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 70 | Open Access | |
Notes | Approved | Most recent IF: 2.068 | |||
Call Number | UA @ admin @ c:irua:165733 | Serial | 6329 | ||
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Author | Milošević, M.V.; Mandrus, D. | ||||
Title | 2D quantum materials : magnetism and superconductivity | Type | A1 Journal article | ||
Year | 2021 | Publication | Journal Of Applied Physics | Abbreviated Journal | J Appl Phys |
Volume | 130 | Issue | 18 | Pages | 180401 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000720289900004 | Publication Date | 2021-11-11 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 2.068 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 2.068 | |||
Call Number | UA @ admin @ c:irua:184090 | Serial | 6963 | ||
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Author | Bafekry, A.; Stampfl, C.; Naseri, M.; Fadlallah, M.M.; Faraji, M.; Ghergherehchi, M.; Gogova, D.; Feghhi, S.A.H. | ||||
Title | Effect of electric field and vertical strain on the electro-optical properties of the MoSi2N4 bilayer : a first-principles calculation | Type | A1 Journal article | ||
Year | 2021 | Publication | Journal Of Applied Physics | Abbreviated Journal | J Appl Phys |
Volume | 129 | Issue | 15 | Pages | 155103 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Recently, a two-dimensional (2D) MoSi 2N 4 (MSN) structure has been successfully synthesized [Hong et al., Science 369(6504), 670-674 (2020)]. Motivated by this result, we investigate the structural, electronic, and optical properties of MSN monolayer (MSN-1L) and bilayer (MSN-2L) under the applied electric field (E-field) and strain using density functional theory calculations. We find that the MSN-2L is a semiconductor with an indirect bandgap of 1.60 (1.80)eV using Perdew-Burke-Ernzerhof (HSE06). The bandgap of MSN-2L decreases as the E-field increases from 0.1 to 0.6V/angstrom and for larger E-field up to 1.0V/angstrom the bilayer becomes metallic. As the vertical strain increases, the bandgap decreases; more interestingly, a semiconductor to a metal phase transition is observed at a strain of 12 %. Furthermore, the optical response of the MSN-2L is in the ultraviolet (UV) region of the electromagnetic spectrum. The absorption edge exhibits a blue shift by applying an E-field or a vertical compressive strain. The obtained interesting properties suggest MSN-2L as a promising material in electro-mechanical and UV opto-mechanical devices. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000640620400003 | Publication Date | 2021-04-15 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 2.068 | |||
Call Number | UA @ admin @ c:irua:178233 | Serial | 6981 | ||
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Author | Osca, J.; Sorée, B. | ||||
Title | Torque field and skyrmion motion by spin transfer torque in a quasi-2D interface in presence of strong spin-orbit interaction | Type | A1 Journal article | ||
Year | 2021 | Publication | Journal Of Applied Physics | Abbreviated Journal | J Appl Phys |
Volume | 130 | Issue | 13 | Pages | 133903 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We investigate the torque field and skyrmion motion at an interface between a ferromagnet hosting a skyrmion and a material with a strong spin-orbit interaction. We analyze both semiconductor materials and topological insulators using a Hamiltonian model that includes a linear term. The spin torque-inducing current is considered to flow in the single band limit; therefore, a quantum model of current is used. Skyrmion motion due to spin transfer torque proves to be more difficult in the presence of a spin-orbit interaction in the case where only interface in-plane currents are present. However, edge effects in narrow nanowires can be used to drive the skyrmion motion and to exert a limited control on its motion direction. We also show the differences and similarities between torque fields due to electric current in the many and single band limits. Published under an exclusive license by AIP Publishing. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000755090400003 | Publication Date | 2021-10-07 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 2.068 | |||
Call Number | UA @ admin @ c:irua:186452 | Serial | 7034 | ||
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Author | Karaaslan, Y.; Haskins, J.B.; Yapicioglu, H.; Sevik, C. | ||||
Title | Influence of randomly distributed vacancy defects on thermal transport in two-dimensional group-III nitrides | Type | A1 Journal article | ||
Year | 2021 | Publication | Journal Of Applied Physics | Abbreviated Journal | J Appl Phys |
Volume | 129 | Issue | 22 | Pages | 224304 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Efficient thermal transport control is a fundamental issue for electronic device applications such as information, communication, and energy storage technologies in modern electronics in order to achieve desired thermal conditions. Structural defects in materials provide a mechanism to adjust the thermal transport properties of these materials on demand. In this context, the effect of structural defects on lattice thermal conductivities of two-dimensional hexagonal binary group-III nitride (XN, X = B, Al, and Ga) semiconductors is systematically investigated by means of classical molecular dynamics simulations performed with recently developed transferable inter-atomic potentials accurately describing defect energies. Here, two different Green-Kubo based approaches and another approach based on non-equilibrium molecular dynamics are compared in order to get an overall understanding. Our investigation clearly shows that defect concentrations of 3% decrease the thermal conductivity of systems containing these nitrites up to 95%. Results hint that structural defects can be used as effective adjustment parameters in controlling thermal transport properties in device applications associated with these materials. Published under an exclusive license by AIP Publishing. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000692024300001 | Publication Date | 2021-06-09 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 2.068 | |||
Call Number | UA @ admin @ c:irua:181618 | Serial | 8096 | ||
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Author | Saiz, F.; Karaaslan, Y.; Rurali, R.; Sevik, C. | ||||
Title | Interatomic potential for predicting the thermal conductivity of zirconium trisulfide monolayers with molecular dynamics | Type | A1 Journal article | ||
Year | 2021 | Publication | Journal Of Applied Physics | Abbreviated Journal | J Appl Phys |
Volume | 129 | Issue | 15 | Pages | 155105 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We present here a new interatomic potential parameter set to predict the thermal conductivity of zirconium trisulfide monolayers. The generated Tersoff-type force field is parameterized using data collected with first-principles calculations. We use non-equilibrium molecular dynamics simulations to predict the thermal conductivity. The generated parameters result in very good agreement in structural, mechanical, and dynamical parameters. The room temperature lattice thermal conductivity ( kappa) of the considered crystal is predicted to be kappa x x = 25.69Wm – 1K – 1 and kappa y y = 42.38Wm – 1K – 1, which both agree well with their corresponding first-principles values with a discrepancy of less than 5%. Moreover, the calculated kappa variation with temperature (200 and 400 K) are comparable within the framework of the accuracy of both first-principles and molecular dynamics simulations. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000641993600001 | Publication Date | 2021-04-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 2.068 | |||
Call Number | UA @ admin @ c:irua:178234 | Serial | 8112 | ||
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Author | Sun, J.; Li, Y.; Karaaslan, Y.; Sevik, C.; Chen, Y. | ||||
Title | Misfit dislocation structure and thermal boundary conductance of GaN/AlN interfaces | Type | A1 Journal article | ||
Year | 2021 | Publication | Journal Of Applied Physics | Abbreviated Journal | J Appl Phys |
Volume | 130 | Issue | 3 | Pages | 035301 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The structure and thermal boundary conductance of the wurtzite GaN/AlN (0001) interface are investigated using molecular dynamics simulation. Simulation results with three different empirical interatomic potentials have produced similar misfit dislocation networks and dislocation core structures. Specifically, the misfit dislocation network at the GaN/AlN interface is found to consist of pure edge dislocations with a Burgers vector of 1/3(1 (2) over bar 10) and the misfit dislocation core has an eight-atom ring structure. Although different interatomic potentials lead to different dislocation properties and thermal conductance values, all have demonstrated a significant effect of misfit dislocations on the thermal boundary conductance of the GaN/AlN (0001) interface. Published under an exclusive license by AIP Publishing. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000694725800001 | Publication Date | 2021-07-15 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 2.068 | |||
Call Number | UA @ admin @ c:irua:181623 | Serial | 8254 | ||
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Author | Bafekry, A.; Shahrokhi, M.; Yagmurcukardes, M.; Gogova, D.; Ghergherehchi, M.; Akgenc, B.; Feghhi, S.A.H. | ||||
Title | Surface functionalization of the honeycomb structure of zinc antimonide (ZnSb) monolayer : a first-principles study | Type | A1 Journal article | ||
Year | 2021 | Publication | Surface Science | Abbreviated Journal | Surf Sci |
Volume | 707 | Issue | Pages | 121796 | |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Structural, electronic, optic and vibrational properties of Zinc antimonide (ZnSb) monolayers and their func-tionalized (semi-fluorinated and fully chlorinated) structures are investigated by means of the first-principles calculations. The phonon dispersion curves reveal the presence of imaginary frequencies and thus confirm the dynamical instability of ZnSb monolayer. The calculated electronic band structure corroborates the metallic character with fully-relativistic calculations. Moreover, we analyze the surface functionalization effect on the structural, vibrational, and electronic properties of the pristine ZnSb monolayer. The semi-fluorinated and fully-chlorinated ZnSb monolayers are shown to be dynamically stable in contrast to the ZnSb monolayer. At the same time, semi-fluorination and fully-chlorination of ZnSb monolayer could effectively modulate the metallic elec-tronic properties of pristine ZnSb. In addition, a magnetic metal to a nonmagnetic semiconductor transition with a band gap of 1 eV is achieved via fluorination, whereas a transition to a semiconducting state with 1.4 eV band gap is found via chlorination of the ZnSb monolayer. According to the optical properties analysis, the first ab-sorption peaks of the fluorinated-and chlorinated-ZnSb monolayers along the in-plane polarization are placed in the infrared range of spectrum, while they are in the middle ultraviolet for the out-of-plane polarization. Interestingly, the optically anisotropic behavior of these novel monolayers along the in-plane polarizations is highly desirable for design of polarization-sensitive photodetectors. The results of the calculations clearly proved that the tunable electronic properties of the ZnSb monolayer can be realized by chemical functionalization for application in the next generation nanoelectronic devices. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000626633500001 | Publication Date | 2020-12-31 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0039-6028 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.062 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 2.062 | |||
Call Number | UA @ admin @ c:irua:177623 | Serial | 7026 | ||
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Author | Saniz, R.; Xu, Y.; Matsubara, M.; Amini, M.N.; Dixit, H.; Lamoen, D.; Partoens, B. | ||||
Title | A simplified approach to the band gap correction of defect formation energies : Al, Ga, and In-doped ZnO | Type | A1 Journal article | ||
Year | 2013 | Publication | The journal of physics and chemistry of solids | Abbreviated Journal | J Phys Chem Solids |
Volume | 74 | Issue | 1 | Pages | 45-50 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | The calculation of defect levels in semiconductors within a density functional theory approach suffers greatly from the band gap problem. We propose a band gap correction scheme that is based on the separation of energy differences in electron addition and relaxation energies. We show that it can predict defect levels with a reasonable accuracy, particularly in the case of defects with conduction band character, and yet is simple and computationally economical. We apply this method to ZnO doped with group III elements (Al, Ga, In). As expected from experiment, the results indicate that Zn substitutional doping is preferred over interstitial doping in Al, Ga, and In-doped ZnO, under both zinc-rich and oxygen-rich conditions. Further, all three dopants act as shallow donors, with the +1 charge state having the most advantageous formation energy. Also, doping effects on the electronic structure of ZnO are sufficiently mild so as to affect little the fundamental band gap and lowest conduction bands dispersion, which secures their n-type transparent conducting behavior. A comparison with the extrapolation method based on LDA+U calculations and with the HeydScuseriaErnzerhof hybrid functional (HSE) shows the reliability of the proposed scheme in predicting the thermodynamic transition levels in shallow donor systems. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000311062500009 | Publication Date | 2012-08-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0022-3697; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.059 | Times cited | 36 | Open Access | |
Notes | Fwo; Bof-Nio | Approved | Most recent IF: 2.059; 2013 IF: 1.594 | ||
Call Number | UA @ lucian @ c:irua:101782 | Serial | 3004 | ||
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Author | Bussmann-Holder, A.; Dalal, N.; Michel, K.H. | ||||
Title | Polarizability induced cooperative proton ordering, coexistence of order/disorder and displacive dynamics and isotope effects in hydrogen-bonded systems | Type | A1 Journal article | ||
Year | 2000 | Publication | The journal of physics and chemistry of solids T2 – Williamsburg Workshop on Ferroelectrics 99, JAN 31-FEB 03, 1999, WILLIAMSBURG, VIRGINIA | Abbreviated Journal | J Phys Chem Solids |
Volume | 61 | Issue | 2 | Pages | 271-274 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Despite the general belief that hydrogen-bonded ferro- and antiferroelectrics undergo a pure order/disorder transition at the structural instability, new NMR data and a new theoretical concept yield convincing evidence that a pronounced displacive component is present in these systems, which modifies substantially the temperature dependencies of the tunnel and lattice mode frequencies. The experiments and their interpretation are presented. (C) 1999 Elsevier Science Ltd. All rights reserved. | ||||
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Corporate Author | Thesis | ||||
Publisher | Pergamon-elsevier science ltd | Place of Publication | Oxford | Editor | |
Language | Wos | 000084147000020 | Publication Date | 2002-07-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0022-3697; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.059 | Times cited | 8 | Open Access | |
Notes | Approved | Most recent IF: 2.059; 2000 IF: 1.003 | |||
Call Number | UA @ lucian @ c:irua:103469 | Serial | 2660 | ||
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Author | Saniz, R.; Sarmadian, N.; Partoens, B.; Batuk, M.; Hadermann, J.; Marikutsa, A.; Rumyantseva, M.; Gaskov, A.; Lamoen, D. | ||||
Title | First-principles study of CO and OH adsorption on in-doped ZnO surfaces | Type | A1 Journal article | ||
Year | 2019 | Publication | The journal of physics and chemistry of solids | Abbreviated Journal | J Phys Chem Solids |
Volume | 132 | Issue | Pages | 172-181 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | We present a first-principles computational study of CO and OH adsorption on non-polar ZnO (10¯10) surfaces doped with indium. The calculations were performed using a model ZnO slab. The position of the In dopants was varied from deep bulk-like layers to the surface layers. It was established that the preferential location of the In atoms is at the surface by examining the dependence of the defect formation energy as well as the surface energy on In location. The adsorption sites on the surface of ZnO and the energy of adsorption of CO molecules and OH-species were determined in connection to In doping. It was found that OH has higher bonding energy to the surface than CO. The presence of In atoms at the surface of ZnO is favorable for CO adsorption, resulting in an elongation of the C-O bond and in charge transfer to the surface. The effect of CO and OH adsorption on the electronic and conduction properties of surfaces was assessed. We conclude that In-doped ZnO surfaces should present a higher electronic response upon adsorption of CO. |
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000472124700023 | Publication Date | 2019-04-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0022-3697 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.059 | Times cited | 7 | Open Access | Not_Open_Access: Available from 26.04.2021 |
Notes | FWO-Vlaanderen, G0D6515N ; ERA.Net RUS Plus, 096 ; VSC; HPC infrastructure of the University of Antwerp; FWO-Vlaanderen; Flemish Government-department EWI; | Approved | Most recent IF: 2.059 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:159656 | Serial | 5170 | ||
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Author | De Beule, C.; Saniz, R.; Partoens, B. | ||||
Title | Crystalline topological states at a topological insulator junction | Type | A1 Journal article | ||
Year | 2019 | Publication | The journal of physics and chemistry of solids | Abbreviated Journal | J Phys Chem Solids |
Volume | 128 | Issue | 128 | Pages | 144-151 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | We consider an interface between two strong time-reversal invariant topological insulators having surface states with opposite spin chirality, or equivalently, opposite mirror Chern number. We show that such an interface supports gapless modes that are protected by mirror symmetry. The interface states are investigated with a continuum model for the Bi2Se3 class of topological insulators that takes into account terms up to third order in the crystal momentum, which ensures that the model has the correct symmetry. The model parameters are obtained from ab initio calculations. Finally, we consider the effect of rotational mismatch at the interface, which breaks the mirror symmetry and opens a gap in the interface spectrum. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000472693100013 | Publication Date | 2018-01-31 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0022-3697 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 2.059 | Times cited | Open Access | ||
Notes | ; ; | Approved | Most recent IF: 2.059 | ||
Call Number | UA @ admin @ c:irua:161391 | Serial | 5385 | ||
Permanent link to this record | |||||
Author | Chaves, A.; Farias, G.A.; Peeters, F.M.; Ferreira, R. | ||||
Title | The Split-operator technique for the study of spinorial wavepacket dynamics | Type | A1 Journal article | ||
Year | 2015 | Publication | Communications in computational physics | Abbreviated Journal | Commun Comput Phys |
Volume | 17 | Issue | 17 | Pages | 850-866 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The split-operator technique for wave packet propagation in quantum systems is expanded here to the case of propagatingwave functions describing Schrodinger particles, namely, charge carriers in semiconductor nanostructures within the effective mass approximation, in the presence of Zeeman effect, as well as of Rashba and Dresselhaus spin-orbit interactions. We also demonstrate that simple modifications to the expanded technique allow us to calculate the time evolution of wave packets describing Dirac particles, which are relevant for the study of transport properties in graphene. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000353695400010 | Publication Date | 2015-03-24 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1815-2406;1991-7120; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.004 | Times cited | 24 | Open Access | |
Notes | ; The authors gratefully acknowledge fruitful discussions with J. M. Pereira Jr. and R. N. Costa Filho. This work was financially supported by CNPq through the INCT-NanoBioSimes and the Science Without Borders programs (contract 402955/ 2012-9), PRONEX/FUNCAP, CAPES, the Bilateral programme between Flanders and Brazil, and the Flemish Science Foundation (FWO-Vl). ; | Approved | Most recent IF: 2.004; 2015 IF: 1.943 | ||
Call Number | c:irua:126028 | Serial | 3593 | ||
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Author | Mattauch, S.; Heger, G.; Michel, K.H. | ||||
Title | High resolution neutron and X-ray diffraction studies as a function of temperature and electric field of the ferroelectric phase transition of RDP | Type | A1 Journal article | ||
Year | 2004 | Publication | Crystal research and technology | Abbreviated Journal | Cryst Res Technol |
Volume | 39 | Issue | 12 | Pages | 1027-1054 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Neutron and high resolution X-ray diffraction investigations on perfect single crystals of RbH2PO4 (RDP), a hydrogen bonded ferroelectric of KDP type are reported. The results of crystal structure analysis from diffraction data, below and above the paraelectric – ferroelectric phase transition, support a disorder – order character Of [PO4H2](-)-groups. The tetragonal symmetry of the paraelectric phase with the double well potential of the hydrogen atoms obtained by diffraction, results simply from a time-space average of orthorhombic symmetry. According to the group – subgroup relation between the tetragonal space group 142d and the orthorhombic Fdd2 a short range order of ferroelectric clusters in the tetragonal phase is observed. With decreasing temperature the ferroelectric clusters increase and the long range interaction between their local polarisation vectors leads to the formation of lamellar ferroelectric domains with alternating polarisation directions at T-C = 147 K. From the high resolution X-ray data it is concluded that below T-C the ferroelastic strain in the (a,b)-plane leads to micro-angle grain boundaries at the domain walls. The tilt angle is enhanced by an applied electric field parallel to the ferroelectric axis. The resulting dislocations at the domain walls persist in the paraelectric phase leading to a memory effect for the arrangement of twin lamellae. With increased electric field the phase transition temperature T-C is decreased. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Berlin | Editor | ||
Language | Wos | 000225681100001 | Publication Date | 2004-11-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0232-1300;1521-4079; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1 | Times cited | 12 | Open Access | |
Notes | Approved | Most recent IF: 1; 2004 IF: 0.770 | |||
Call Number | UA @ lucian @ c:irua:94785 | Serial | 1459 | ||
Permanent link to this record | |||||
Author | Yan, X.F.; Chen, Q.; Li, L.L.; Guo, H.Z.; Peng, J.Z.; Peeters, F.M. | ||||
Title | High performance piezotronic spin transistors using molybdenum disulfide nanoribbon | Type | A1 Journal article | ||
Year | 2020 | Publication | Nano Energy | Abbreviated Journal | Nano Energy |
Volume | 75 | Issue | Pages | 104953 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | Two-dimensional (2D) materials are promising candidates for atomic-scale piezotronics and piezophototronics. Quantum edge states show fascinating fundamental physics such as nontrivial topological behavior and hold promising practical applications for low-power electronic devices. Here, using the tight-binding approach and quantum transport simulations, we investigate the piezotronic effect on the spin polarization of edge states in a zigzag-terminated monolayer MoS2 nanoribbon. We find that the strain-induced piezoelectric potential induces a phase transition of edge states from metal to semiconductor. However, in the presence of exchange field, edge states become semi-metallic with significant spin splitting and polarization that can be tuned by external strain. We show that quantum transport conductance exhibits a 100% spin polarization over a wide range of strain magnitudes. This effect is used in a propose prototype of piezotronic spin transistor. Our results provide a fundamental understanding of the piezotronic effect on edge states in zigzag monolayer MoS2 nanoribbons and are relevant for designing high-performance piezotronic spin devices. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000560729200011 | Publication Date | 2020-05-24 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2211-2855 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 17.6 | Times cited | 20 | Open Access | |
Notes | ; This work was supported by Hunan Provincial Natural Science Foundation of China (Nos. 2015JJ2040, 2018JJ2078), Scientific Research Fund of Hunan Provincial Education Department (19A106), and the Funeral Service Foundation (FWO-VI). ; | Approved | Most recent IF: 17.6; 2020 IF: 12.343 | ||
Call Number | UA @ admin @ c:irua:171123 | Serial | 6535 | ||
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Author | Sethu, K.K.V.; Yasin, F.; Swerts, J.; Sorée, B.; De Boeck, J.; Kar, G.S.; Garello, K.; Couet, S. | ||||
Title | Spin-orbit torque vector quantification in nanoscale magnetic tunnel junctions | Type | A1 Journal article | ||
Year | 2024 | Publication | ACS nano | Abbreviated Journal | |
Volume | 18 | Issue | 21 | Pages | 13506-13516 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | Spin-orbit torques (SOT) allow ultrafast, energy-efficient toggling of magnetization state by an in-plane charge current for applications such as magnetic random-access memory (SOT-MRAM). Tailoring the SOT vector comprising of antidamping (T-AD) and fieldlike (T-FL) torques could lead to faster, more reliable, and low-power SOT-MRAM. Here, we establish a method to quantify the longitudinal (T-AD) and transverse (T-FL) components of the SOT vector and its efficiency chi(AD) and chi(FL), respectively, in nanoscale three-terminal SOT magnetic tunnel junctions (SOT-MTJ). Modulation of nucleation or switching field (B-SF) for magnetization reversal by SOT effective fields (B-SOT) leads to the modification of SOT-MTJ hysteresis loop behavior from which chi(AD) and chi(FL) are quantified. Surprisingly, in nanoscale W/CoFeB SOT-MTJ, we find chi(FL) to be (i) twice as large as chi(AD) and (ii) 6 times as large as chi(FL) in micrometer-sized W/CoFeB Hall-bar devices. Our quantification is supported by micromagnetic and macrospin simulations which reproduce experimental SOT-MTJ Stoner-Wohlfarth astroid behavior only for chi(FL) > chi(AD). Additionally, from the threshold current for current-induced magnetization switching with a transverse magnetic field, we show that in SOT-MTJ, T-FL plays a more prominent role in magnetization dynamics than T-AD. Due to SOT-MRAM geometry and nanodimensionality, the potential role of nonlocal spin Hall spin current accumulated adjacent to the SOT-MTJ in the mediation of T-FL and chi(FL) amplification merits to be explored. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 001226121700001 | Publication Date | 2024-05-15 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 17.1 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 17.1; 2024 IF: 13.942 | |||
Call Number | UA @ admin @ c:irua:205980 | Serial | 9173 | ||
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Author | Zhang, G.; Huang, S.; Chaves, A.; Yan, H. | ||||
Title | Black phosphorus as tunable Van der Waals quantum wells with high optical quality | Type | A1 Journal article | ||
Year | 2023 | Publication | ACS nano | Abbreviated Journal | |
Volume | 17 | Issue | 6 | Pages | 6073-6080 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | Van der Waals quantum wells, naturally formed in two-dimensional layered materials with nanoscale thickness, possess many inherent advantages over conventional molecular beam epitaxy grown counterparts, and could bring up intriguing physics and applications. However, optical transitions originated from the series of quantized states in these emerging quantum wells are still elusive. Here, we show that multilayer black phosphorus appears to be an excellent candidate for van der Waals quantum wells with well-defined subbands and high optical quality. Using infrared absorption spectroscopy, we probe subband structures of multilayer black phosphorus with tens of atomic layers, revealing clear signatures for optical transitions with subband index as high as 10, far from what was attainable previously. Surprisingly, in addition to allowed transitions, an unexpected series of “forbidden” transitions is also evidently observed, which enables us to determine energy spacings separately for conduction and valence subbands. Furthermore, the linear tunability of subband spacings by temperature and strain is demonstrated. Our results are expected to facilitate potential applications for infrared optoelectronics based on tunable van der Waals quantum wells. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000953463300001 | Publication Date | 2023-03-13 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 17.1 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 17.1; 2023 IF: 13.942 | |||
Call Number | UA @ admin @ c:irua:196100 | Serial | 7565 | ||
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Author | Tran, T.T.; Lee, Y.; Roy, S.; Tran, T.U.; Kim, Y.; Taniguchi, T.; Watanabe, K.; Milošević, M.V.; Lim, S.C.; Chaves, A.; Jang, J.I.; Kim, J. | ||||
Title | Synergetic enhancement of quantum yield and exciton lifetime of monolayer WS₂ by proximal metal plate and negative electric bias | Type | A1 Journal article | ||
Year | 2023 | Publication | ACS nano | Abbreviated Journal | |
Volume | 18 | Issue | 1 | Pages | 220-228 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | The efficiency of light emission is a critical performance factor for monolayer transition metal dichalcogenides (1L-TMDs) for photonic applications. While various methods have been studied to compensate for lattice defects to improve the quantum yield (QY) of 1L-TMDs, exciton-exciton annihilation (EEA) is still a major nonradiative decay channel for excitons at high exciton densities. Here, we demonstrate that the combined use of a proximal Au plate and a negative electric gate bias (NEGB) for 1L-WS2 provides a dramatic enhancement of the exciton lifetime at high exciton densities with the corresponding QY enhanced by 30 times and the EEA rate constant decreased by 80 times. The suppression of EEA by NEGB is attributed to the reduction of the defect-assisted EEA process, which we also explain with our theoretical model. Our results provide a synergetic solution to cope with EEA to realize high-intensity 2D light emitters using TMDs. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 001139516800001 | Publication Date | 2023-12-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 17.1 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 17.1; 2023 IF: 13.942 | |||
Call Number | UA @ admin @ c:irua:202811 | Serial | 9101 | ||
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Author | Griffin, E.; Mogg, L.; Hao, G.-P.; Kalon, G.; Bacaksiz, C.; Lopez-Polin, G.; Zhou, T.Y.; Guarochico, V.; Cai, J.; Neumann, C.; Winter, A.; Mohn, M.; Lee, J.H.; Lin, J.; Kaiser, U.; Grigorieva, I., V; Suenaga, K.; Ozyilmaz, B.; Cheng, H.-M.; Ren, W.; Turchanin, A.; Peeters, F.M.; Geim, A.K.; Lozada-Hidalgo, M. | ||||
Title | Proton and Li-Ion permeation through graphene with eight-atom-ring defects | Type | A1 Journal article | ||
Year | 2020 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
Volume | 14 | Issue | 6 | Pages | 7280-7286 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | Defect-free graphene is impermeable to gases and liquids but highly permeable to thermal protons. Atomic-scale defects such as vacancies, grain boundaries, and Stone-Wales defects are predicted to enhance graphene's proton permeability and may even allow small ions through, whereas larger species such as gas molecules should remain blocked. These expectations have so far remained untested in experiment. Here, we show that atomically thin carbon films with a high density of atomic-scale defects continue blocking all molecular transport, but their proton permeability becomes similar to 1000 times higher than that of defect-free graphene. Lithium ions can also permeate through such disordered graphene. The enhanced proton and ion permeability is attributed to a high density of eight-carbon-atom rings. The latter pose approximately twice lower energy barriers for incoming protons compared to that of the six-atom rings of graphene and a relatively low barrier of similar to 0.6 eV for Li ions. Our findings suggest that disordered graphene could be of interest as membranes and protective barriers in various Li-ion and hydrogen technologies. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000543744100086 | Publication Date | 2020-05-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 17.1 | Times cited | 53 | Open Access | |
Notes | ; The work was supported by the Lloyd's Register Foundation, EPSRC-EP/N010345/1, the European Research Council, the Graphene Flagship, the Deutsche Forschungsgemeinschaft project TRR 234 “CataLight” (Project B7, Grant No. 364549901), and the research infrastructure Grant No. INST 275/25 7-1 FUGG. E.G. and L.M. acknowledge the EPSRC NowNANO programme for funding. ; | Approved | Most recent IF: 17.1; 2020 IF: 13.942 | ||
Call Number | UA @ admin @ c:irua:170708 | Serial | 6586 | ||
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Author | Huang, S.; Griffin, E.; Cai, J.; Xin, B.; Tong, J.; Fu, Y.; Kravets, V.; Peeters, F.M.; Lozada-Hidalgo, M. | ||||
Title | Gate-controlled suppression of light-driven proton transport through graphene electrodes | Type | A1 Journal article | ||
Year | 2023 | Publication | Nature communications | Abbreviated Journal | |
Volume | 14 | Issue | 1 | Pages | 6932-6937 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | Recent experiments demonstrated that proton transport through graphene electrodes can be accelerated by over an order of magnitude with low intensity illumination. Here we show that this photo-effect can be suppressed for a tuneable fraction of the infra-red spectrum by applying a voltage bias. Using photocurrent measurements and Raman spectroscopy, we show that such fraction can be selected by tuning the Fermi energy of electrons in graphene with a bias, a phenomenon controlled by Pauli blocking of photo-excited electrons. These findings demonstrate a dependence between graphene's electronic and proton transport properties and provide fundamental insights into molecularly thin electrode-electrolyte interfaces and their interaction with light. Recent experiments have shown that proton transport through graphene electrodes can be promoted by light, but the understanding of this phenomenon remains unclear. Here, the authors report the electrical tunability of this photo-effect, showing a connection between graphene electronic and proton transport properties. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 001094448600003 | Publication Date | 2023-10-31 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 16.6 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 16.6; 2023 IF: 12.124 | |||
Call Number | UA @ admin @ c:irua:201185 | Serial | 9041 | ||
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Author | Cai, J.; Griffin, E.; Guarochico-Moreira, V.H.; Barry, D.; Xin, B.; Yagmurcukardes, M.; Zhang, S.; Geim, A.K.; Peeters, F.M.; Lozada-Hidalgo, M. | ||||
Title | Wien effect in interfacial water dissociation through proton-permeable graphene electrodes | Type | A1 Journal article | ||
Year | 2022 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
Volume | 13 | Issue | 1 | Pages | 5776-5777 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | Strong electric fields can accelerate molecular dissociation reactions. The phenomenon known as the Wien effect was previously observed using high-voltage electrolysis cells that produced fields of about 10(7) V m(-1), sufficient to accelerate the dissociation of weakly bound molecules (e.g., organics and weak electrolytes). The observation of the Wien effect for the common case of water dissociation (H2O reversible arrow H+ + OH-) has remained elusive. Here we study the dissociation of interfacial water adjacent to proton-permeable graphene electrodes and observe strong acceleration of the reaction in fields reaching above 10(8) V m(-1). The use of graphene electrodes allows measuring the proton currents arising exclusively from the dissociation of interfacial water, while the electric field driving the reaction is monitored through the carrier density induced in graphene by the same field. The observed exponential increase in proton currents is in quantitative agreement with Onsager's theory. Our results also demonstrate that graphene electrodes can be valuable for the investigation of various interfacial phenomena involving proton transport. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000862552600012 | Publication Date | 2022-10-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 16.6 | Times cited | 14 | Open Access | OpenAccess |
Notes | Approved | Most recent IF: 16.6 | |||
Call Number | UA @ admin @ c:irua:191575 | Serial | 7228 | ||
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Author | Zhou, Z.; Tan, Y.; Yang, Q.; Bera, A.; Xiong, Z.; Yagmurcukardes, M.; Kim, M.; Zou, Y.; Wang, G.; Mishchenko, A.; Timokhin, I.; Wang, C.; Wang, H.; Yang, C.; Lu, Y.; Boya, R.; Liao, H.; Haigh, S.; Liu, H.; Peeters, F.M.; Li, Y.; Geim, A.K.; Hu, S. | ||||
Title | Gas permeation through graphdiyne-based nanoporous membranes | Type | A1 Journal article | ||
Year | 2022 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
Volume | 13 | Issue | 1 | Pages | 4031-4036 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | Nanoporous membranes based on two dimensional materials are predicted to provide highly selective gas transport in combination with extreme permeance. Here we investigate membranes made from multilayer graphdiyne, a graphene-like crystal with a larger unit cell. Despite being nearly a hundred of nanometers thick, the membranes allow fast, Knudsen-type permeation of light gases such as helium and hydrogen whereas heavy noble gases like xenon exhibit strongly suppressed flows. Using isotope and cryogenic temperature measurements, the seemingly conflicting characteristics are explained by a high density of straight-through holes (direct porosity of similar to 0.1%), in which heavy atoms are adsorbed on the walls, partially blocking Knudsen flows. Our work offers important insights into intricate transport mechanisms playing a role at nanoscale. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000918423100001 | Publication Date | 2022-07-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 16.6 | Times cited | 21 | Open Access | OpenAccess |
Notes | Approved | Most recent IF: 16.6 | |||
Call Number | UA @ admin @ c:irua:194402 | Serial | 7308 | ||
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Author | Tang, C.S.; Zeng, S.; Wu, J.; Chen, S.; Naradipa, M.A.; Song, D.; Milošević, M.V.; Yang, P.; Diao, C.; Zhou, J.; Pennycook, S.J.; Breese, M.B.H.; Cai, C.; Venkatesan, T.; Ariando, A.; Yang, M.; Wee, A.T.S.; Yin, X. | ||||
Title | Detection of two-dimensional small polarons at oxide interfaces by optical spectroscopy | Type | A1 Journal article | ||
Year | 2023 | Publication | Applied physics reviews | Abbreviated Journal | |
Volume | 10 | Issue | 3 | Pages | 031406-31409 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Two-dimensional (2D) perovskite oxide interfaces are ideal systems to uncover diverse emergent properties, such as the arising polaronic properties from short-range charge-lattice interactions. Thus, a technique to detect this quasiparticle phenomenon at the buried interface is highly coveted. Here, we report the observation of 2D small-polarons at the LaAlO3/SrTiO3 conducting interface using high-resolution spectroscopic ellipsometry. First-principles investigations show that interfacial electron-lattice coupling mediated by the longitudinal phonon mode facilitates the formation of these polarons. This study resolves the long-standing question by attributing the formation of interfacial 2D small polarons to the significant mismatch between experimentally measured interfacial carrier density and theoretical values. Our study sheds light on the complexity of broken periodic lattice-induced quasi-particle effects and its relationship with exotic phenomena at complex oxide interfaces. Meanwhile, this work establishes spectroscopic ellipsometry as a useful technique to detect and locate optical evidence of polaronic states and other emerging quantum properties at the buried interface. | ||||
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Language | Wos | 001038283300001 | Publication Date | 2023-09-06 | |
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ISSN | 1931-9401 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 15; 2023 IF: 13.667 | |||
Call Number | UA @ admin @ c:irua:198433 | Serial | 8847 | ||
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Author | Yagmurcukardes, M.; Qin, Y.; Ozen, S.; Sayyad, M.; Peeters, F.M.; Tongay, S.; Sahin, H. | ||||
Title | Quantum properties and applications of 2D Janus crystals and their superlattices | Type | A1 Journal article | ||
Year | 2020 | Publication | Applied Physics Reviews | Abbreviated Journal | Appl Phys Rev |
Volume | 7 | Issue | 1 | Pages | 011311-11316 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Two-dimensional (2D) Janus materials are a new class of materials with unique physical, chemical, and quantum properties. The name “Janus” originates from the ancient Roman god which has two faces, one looking to the future while the other facing the past. Janus has been used to describe special types of materials which have two faces at the nanoscale. This unique atomic arrangement has been shown to present rather exotic properties with applications in biology, chemistry, energy conversion, and quantum sciences. This review article aims to offer a comprehensive review of the emergent quantum properties of Janus materials. The review starts by introducing 0D Janus nanoparticles and 1D Janus nanotubes, and highlights their difference from classical ones. The design principles, synthesis, and the properties of graphene-based and chalcogenide-based Janus layers are then discussed. A particular emphasis is given to colossal built-in potential in 2D Janus layers and resulting quantum phenomena such as Rashba splitting, skyrmionics, excitonics, and 2D magnetic ordering. More recent theoretical predictions are discussed in 2D Janus superlattices when Janus layers are stacked onto each other. Finally, we discuss the tunable quantum properties and newly predicted 2D Janus layers waiting to be experimentally realized. The review serves as a complete summary of the 2D Janus library and predicted quantum properties in 2D Janus layers and their superlattices. | ||||
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Language | Wos | 000519611500001 | Publication Date | 2020-02-21 | |
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ISSN | 1931-9401 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15 | Times cited | 158 | Open Access | |
Notes | ; S.T. acknowledges support from NSF Contract Nos. DMR 1552220, DMR 1904716, and NSF CMMI 1933214. H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 117F095. H.S. acknowledges support from the Turkish Academy of Sciences under the GEBIP program. M.Y. is supported by the Flemish Science Foundation (FWO-Vl) through a postdoctoral fellowship. Part of this work was supported by the FLAG-ERA project TRANS2D-TMD. ; | Approved | Most recent IF: 15; 2020 IF: 13.667 | ||
Call Number | UA @ admin @ c:irua:167712 | Serial | 6591 | ||
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