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| Author | Bacaksiz, C.; Šabani, D.; Menezes, R.M.; Milošević, M.V. | ||||
| Title | Distinctive magnetic properties of CrI3 and CrBr3 monolayers caused by spin-orbit coupling | Type | A1 Journal article | ||
| Year | 2021 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 103 | Issue | 12 | Pages | 125418 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | After the discovery of magnetism in monolayer CrI3, the magnetic properties of different 2D materials from the chromium-trihalide family are intuitively assumed to be similar, yielding magnetic anisotropy from the spin-orbit coupling on halide ligands. Here we reveal significant differences between the CrI3 and CrBr3 magnetic monolayers in their magnetic anisotropy, resulting Curie temperature, hysteresis in external magnetic field, and evolution of magnetism with strain, all predominantly attributed to distinctly different interplay of atomic contributions to spin-orbit coupling in two materials. | ||||
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| Language | Wos | 000646179300003 | Publication Date | 2021-03-17 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 18 | Open Access | OpenAccess |
| Notes | Fonds Wetenschappelijk Onderzoek; Universiteit Antwerpen; | Approved  |
Most recent IF: 3.836 | ||
| Call Number | CMT @ cmt @c:irua:177506 | Serial | 6756 | ||
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| Author | Cunha, S.M.; de Costa, D.R.; Pereira Jr, J.M.; Costa Filho, R.N.; Van Duppen, B.; Peeters, F.M. | ||||
| Title | Band-gap formation and morphing in alpha-T-3 superlattices | Type | A1 Journal article | ||
| Year | 2021 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 104 | Issue | 11 | Pages | 115409 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Electrons in alpha-T-3 lattices behave as condensed-matter analogies of integer-spin Dirac fermions. The three atoms making up the unit cell bestow the energy spectrum with an additional energy band that is completely flat, providing unique electronic properties. The interatomic hopping term, alpha, is known to strongly affect the electronic spectrum of the two-dimensional (2D) lattice, allowing it to continuously morph from graphenelike responses to the behavior of fermions in a dice lattice. For pristine lattice structures the energy bands are gapless, but small deviations in the atomic equivalence of the three sublattices will introduce gaps in the spectrum. It is unknown how these affect transport and electronic properties such as the energy spectrum of superlattice minibands. Here we investigate the dependency of these properties on the parameter a accounting for different symmetry-breaking terms, and we show how it affects band-gap formation. Furthermore, we find that superlattices can force band gaps to close and shift in energy. Our results demonstrate that alpha-T-3 superlattices provide a versatile material for 2D band-gap engineering purposes. | ||||
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| Language | Wos | 000696091600003 | Publication Date | 2021-09-10 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 9 | Open Access | OpenAccess |
| Notes | Approved |
Most recent IF: 3.836 | |||
| Call Number | UA @ admin @ c:irua:181544 | Serial | 6972 | ||
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| Author | Vanderveken, F.; Mulkers, J.; Leliaert, J.; Van Waeyenberge, B.; Sorée, B.; Zografos, O.; Ciubotaru, F.; Adelmann, C. | ||||
| Title | Confined magnetoelastic waves in thin waveguides | Type | A1 Journal article | ||
| Year | 2021 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 103 | Issue | 5 | Pages | 054439 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | The characteristics of confined magnetoelastic waves in nanoscale ferromagnetic magnetostrictive waveguides have been investigated by a combination of analytical and numerical calculations. The presence of both magnetostriction and inverse magnetostriction leads to the coupling between confined spin waves and elastic Lamb waves. Numerical simulations of the coupled system have been used to extract the dispersion relations of the magnetoelastic waves as well as their mode profiles. | ||||
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| Language | Wos | 000627548800003 | Publication Date | 2021-02-26 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | Open Access | OpenAccess | |
| Notes | Approved |
Most recent IF: 3.836 | |||
| Call Number | UA @ admin @ c:irua:177607 | Serial | 6976 | ||
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| Author | Pandey, T.; Covaci, L.; Milošević, M.V.; Peeters, F.M. | ||||
| Title | Flexoelectricity and transport properties of phosphorene nanoribbons under mechanical bending | Type | A1 Journal article | ||
| Year | 2021 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 103 | Issue | 23 | Pages | 235406 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | We examine from first principles the flexoelectric properties of phosphorene nanoribbons under mechanical bending along armchair and zigzag directions. In both cases we find that the radial polarization depends linearly on the strain gradient. The flexoelectricity along the armchair direction is over 40% larger than along the zigzag direction. The obtained flexoelectric coefficients of phosphorene are four orders of magnitude larger than those of graphene and comparable to transition metal dichalcogenides. Analysis of charge density shows that the flexoelectricity mainly arises from the pz orbitals of phosphorus atoms. The electron mobilities in bent phosphorene can be enhanced by over 60% along the armchair direction, which is significantly higher than previous reports of mobility tuned by uniaxial strain. Our results indicate phosphorene is a candidate for a two-dimensional material applicable in flexible-electronic devices. | ||||
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| Language | Wos | 000657129800006 | Publication Date | 2021-06-02 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 12 | Open Access | Not_Open_Access |
| Notes | Approved |
Most recent IF: 3.836 | |||
| Call Number | UA @ admin @ c:irua:179109 | Serial | 6996 | ||
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| Author | Miranda, L.P.; Milovanović, S.P.; Filho, R.N.C.; Peeters, F.M. | ||||
| Title | Hall and bend resistance of a phosphorene Hall bar | Type | A1 Journal article | ||
| Year | 2021 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 104 | Issue | 3 | Pages | 035401 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | The dependence of the Hall and bend resistances on a perpendicular magnetic field and on vacancy defects in a four-terminal phosphorene single layer Hall bar is investigated. A tight-binding model in combination with the Landauer-Buttiker formalism is used to calculate the energy spectrum, the lead-to-lead transmissions, and the Hall and bend resistances of the system. It is shown that the terminals with zigzag edge orientation are responsible for the absence of quantized plateaus in the Hall resistance and peaks in the longitudinal resistance. A negative bend resistance in the ballistic regime is found due to the presence of high- and low-energy transport modes in the armchair and zigzag terminals, respectively. The system density of states, with single vacancy defects, shows that the presence of in-gap states is proportional to the number of vacancies. Quantized plateaus in the Hall resistance are only formed in a sufficiently clean system. The effects of different kinds of vacancies where the plateaus are destroyed and a diffusive regime appears in the bend resistance are investigated. | ||||
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| Language | Wos | 000669002000003 | Publication Date | 2021-07-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 2 | Open Access | OpenAccess |
| Notes | Approved |
Most recent IF: 3.836 | |||
| Call Number | UA @ admin @ c:irua:179704 | Serial | 6997 | ||
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| Author | Varjovi, M.J.; Yagmurcukardes, M.; Peeters, F.M.; Durgun, E. | ||||
| Title | Janus two-dimensional transition metal dichalcogenide oxides: First-principles investigation of WXO monolayers with X = S, Se, and Te | Type | A1 Journal article | ||
| Year | 2021 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 103 | Issue | 19 | Pages | 195438 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Structural symmetry breaking in two-dimensional materials can lead to superior physical properties and introduce an additional degree of piezoelectricity. In the present paper, we propose three structural phases (1H, 1T, and 1T') of Janus WXO (X = S, Se, and Te) monolayers and investigate their vibrational, thermal, elastic, piezoelectric, and electronic properties by using first-principles methods. Phonon spectra analysis reveals that while the 1H phase is dynamically stable, the 1T phase exhibits imaginary frequencies and transforms to the distorted 1T' phase. Ab initio molecular dynamics simulations confirm that 1H- and 1T'-WXO monolayers are thermally stable even at high temperatures without any significant structural deformations. Different from binary systems, additional Raman active modes appear upon the formation of Janus monolayers. Although the mechanical properties of 1H-WXO are found to be isotropic, they are orientation dependent for 1T'-WXO. It is also shown that 1H-WXO monolayers are indirect band-gap semiconductors and the band gap narrows down the chalcogen group. Except 1T'-WSO, 1T'-WXO monolayers have a narrow band gap correlated with the Peierls distortion. The effect of spin-orbit coupling on the band structure is also examined for both phases and the alteration in the band gap is estimated. The versatile mechanical and electronic properties of Janus WXO monolayers together with their large piezoelectric response imply that these systems are interesting for several nanoelectronic applications. | ||||
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| Language | Wos | 000655902600004 | Publication Date | 2021-05-26 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 78 | Open Access | Not_Open_Access |
| Notes | Approved |
Most recent IF: 3.836 | |||
| Call Number | UA @ admin @ c:irua:179050 | Serial | 7000 | ||
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| Author | Motta, M.; Burger, L.; Jiang, L.; Acosta, J.D.G.; Jelić, Ž.L.; Colauto, F.; Ortiz, W.A.; Johansen, T.H.; Milošević, M.V.; Cirillo, C.; Attanasio, C.; Xue, C.; Silhanek, A., V.; Vanderheyden, B. | ||||
| Title | Metamorphosis of discontinuity lines and rectification of magnetic flux avalanches in the presence of noncentrosymmetric pinning forces | Type | A1 Journal article | ||
| Year | 2021 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 103 | Issue | 22 | Pages | 224514 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Considering a noncentrosymmetric pinning texture composed of a square array of triangular holes, the magnetic flux penetration and expulsion are investigated experimentally and theoretically. A direct visualization of the magnetic landscape obtained using a magneto-optical technique on a Nb film is complemented by a multiscale numerical modeling. This combined approach allows the magnetic flux dynamics to be identified from the single flux quantum limit up to the macroscopic electromagnetic response. Within the theoretical framework provided by time-dependent Ginzburg-Landau simulations, an estimation of the in-plane current anisotropy is obtained and its dependence with the radius of the curvature of hole vertices is addressed. These simulations show that current crowding plays an important role in channeling the flux motion, favoring hole-to-hole flux hopping rather than promoting interstitial flux displacement in between the holes. The resulting anisotropy of the critical current density gives rise to a distinct pattern of discontinuity lines for increasing and decreasing applied magnetic fields, in sharp contrast to the invariable patterns reported for centrosymmetric pinning potentials. This observation is partially accounted for by the rectification effect, as demonstrated by finite-element modeling. At low temperatures, where magnetic field penetration is dominated by thermomagnetic instabilities, highly directional magnetic flux avalanches with a fingerlike shape are observed to propagate along the easy axis of the pinning potential. This morphology is reproduced by numerical simulations. Our findings demonstrate that anisotropic pinning landscapes and, in particular, ratchet potentials produce subtle modifications to the critical state field profile that are reflected in the distribution of discontinuity lines. | ||||
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| Language | Wos | 000687246200001 | Publication Date | 2021-06-09 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 6 | Open Access | OpenAccess |
| Notes | Approved |
Most recent IF: 3.836 | |||
| Call Number | UA @ admin @ c:irua:181714 | Serial | 7002 | ||
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| Author | Yagmurcukardes, M.; Mogulkoc, Y.; Akgenc, B.; Mogulkoc, A.; Peeters, F.M. | ||||
| Title | Prediction of monoclinic single-layer Janus Ga₂ Te X (X = S and Se) : strong in-plane anisotropy | Type | A1 Journal article | ||
| Year | 2021 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 104 | Issue | 4 | Pages | 045425 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | By using density functional theory (DFT) based first-principles calculations, electronic, vibrational, piezo-electric, and optical properties of monoclinic Janus single-layer Ga2TeX (X = S or Se) are investigated. The dynamical, mechanical, and thermal stability of the proposed Janus single layers are verified by means of phonon bands, stiffness tensor, and quantum molecular dynamics simulations. The calculated vibrational spectrum reveals the either pure or coupled optical phonon branches arising from Ga-Te and Ga-X atoms. In addition to the in-plane anisotropy, single-layer Janus Ga2TeX exhibits additional out-of-plane asymmetry, which leads to important consequences for its electronic and optical properties. Electronic band dispersions indicate the direct band-gap semiconducting nature of the constructed Janus structures with energy band gaps falling into visible spectrum. Moreover, while orientation-dependent linear-elastic properties of Janus single layers indicate their strong anisotropy, the calculated in-plane stiffness values reveal the ultrasoft nature of the structures. In addition, predicted piezoelectric coefficients show that while there is a strong in-plane anisotropy between piezoelectric constants along armchair (AC) and zigzag (ZZ) directions, there exists a tiny polarization along the out-of-plane direction as a result of the formation of Janus structure. The optical response to electromagnetic radiation has been also analyzed through density functional theory by considering the independent-particle approximation. Finally, the optical spectra of Janus Ga2TeX structures is investigated and it showed a shift from the ultraviolet region to the visible region. The fact that the spectrum is between these regions will allow it to be used in solar energy and many nanoelectronics applications. The predicted monoclinic single-layer Janus Ga2TeX are relevant for promising applications in optoelectronics, optical dichroism, and anisotropic nanoelasticity. | ||||
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| Language | Wos | 000678811100007 | Publication Date | 2021-07-26 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 14 | Open Access | Not_Open_Access |
| Notes | Approved |
Most recent IF: 3.836 | |||
| Call Number | UA @ admin @ c:irua:180404 | Serial | 7013 | ||
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| Author | Mijin, S.D.; Baum, A.; Bekaert, J.; Solajic, A.; Pesic, J.; Liu, Y.; He, G.; Milošević, M.V.; Petrovic, C.; Popovic, Z., V; Hackl, R.; Lazarevic, N. | ||||
| Title | Probing charge density wave phases and the Mott transition in 1T-TaS₂I by inelastic light scattering | Type | A1 Journal article | ||
| Year | 2021 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 103 | Issue | 24 | Pages | 245133 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | We present a polarization-resolved, high-resolution Raman scattering study of the three consecutive charge density wave (CDW) regimes in 1T-TaS2 single crystals, supported by ab initio calculations. Our analysis of the spectra within the low-temperature commensurate (C-CDW) regime shows P (3) over bar symmetry of the system, thus excluding the previously proposed triclinic stacking of the “star-of-David” structure, and promoting trigonal or hexagonal stacking instead. The spectra of the high-temperature incommensurate (IC-CDW) phase directly project the phonon density of states due to the breaking of the translational invariance, supplemented by sizable electron-phonon coupling. Between 200 and 352 K, our Raman spectra show contributions from both the IC-CDW and the C-CDW phases, indicating their coexistence in the so-called nearly commensurate (NC-CDW) phase. The temperature dependence of the symmetry-resolved Raman conductivity indicates the stepwise reduction of the density of states in the CDW phases, followed by a Mott transition within the C-CDW phase. We determine the size of the Mott gap to be Omega(gap) approximate to 170-190 meV, and track its temperature dependence. | ||||
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| Language | Wos | 000664450500002 | Publication Date | 2021-06-22 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 4 | Open Access | OpenAccess |
| Notes | Approved |
Most recent IF: 3.836 | |||
| Call Number | UA @ admin @ c:irua:179664 | Serial | 7015 | ||
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| Author | van Duijn, F.; Osca, J.; Sorée, B. | ||||
| Title | Skyrmion elongation, duplication, and rotation by spin-transfer torque under spatially varying spin current | Type | A1 Journal article | ||
| Year | 2021 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 104 | Issue | 9 | Pages | 094426 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | The effect of the spatially varying spin current on a skyrmion is numerically investigated. It is shown that an inhomogeneous current density induces an elongation of the skyrmion. This elongation can be controlled using current pulses of different strength and duration. Long current pulses lead to a splitting that forms two replicas of the initial skyrmion while for short pulses the elongated skyrmion relaxes back to its initial circular state through rotation in the MHz-GHz frequency range. The frequency is dependent on the strength of the damping coefficient. | ||||
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| Language | Wos | 000704236000002 | Publication Date | 2021-09-21 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | Open Access | OpenAccess | |
| Notes | Approved |
Most recent IF: 3.836 | |||
| Call Number | UA @ admin @ c:irua:182467 | Serial | 7018 | ||
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| Author | Man, L.F.; Xu, W.; Xiao, Y.M.; Wen, H.; Ding, L.; Van Duppen, B.; Peeters, F.M. | ||||
| Title | Terahertz magneto-optical properties of graphene hydrodynamic electron liquid | Type | A1 Journal article | ||
| Year | 2021 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 104 | Issue | 12 | Pages | 125420 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | The discovery of the hydrodynamic electron liquid (HEL) in graphene [D. Bandurin et al., Science 351, 1055 (2016) and J. Crossno et al., Science 351, 1058 (2016)] has marked the birth of the solid-state HEL which can be probed near room temperature in a table-top setup. Here we examine the terahertz (THz) magneto-optical (MO) properties of a graphene HEL. Considering the case where the magnetic length l(B) = root h/eB is comparable to the mean-free path l(ee) for electron-electron interaction in graphene, the MO conductivities are obtained by taking a momentum balance equation approach on the basis of the Boltzmann equation. We find that when l(B) similar to l(ee), the viscous effect in a HEL can weaken significantly the THz MO effects such as cyclotron resonance and Faraday rotation. The upper hybrid and cyclotron resonance magnetoplasmon modes omega(+/-) are also obtained through the RPA dielectric function. The magnetoplasmons of graphene HEL at large wave-vector regime are affected by the viscous effect, and results in red-shifts of the magnetoplasmon frequencies. We predict that the viscosity in graphene HEL can affect strongly the magneto-optical and magnetoplasmonic properties, which can be verified experimentally. | ||||
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| Language | Wos | 000704419300004 | Publication Date | 2021-09-15 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 4 | Open Access | OpenAccess |
| Notes | Approved |
Most recent IF: 3.836 | |||
| Call Number | UA @ admin @ c:irua:182518 | Serial | 7029 | ||
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| Author | Demiroglu, I.; Sevik, C. | ||||
| Title | Extraordinary negative thermal expansion of two-dimensional nitrides : a comparative ab initio study of quasiharmonic approximation and molecular dynamics simulations | Type | A1 Journal article | ||
| Year | 2021 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 103 | Issue | 8 | Pages | 085430 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Thermal expansion behavior of two-dimensional (2D) nitrides and graphene were studied by ab initio molecular dynamics (MD) simulations as well as quasiharmonic approximation (QHA). Anharmonicity of the acoustic phonon modes are related to the unusual negative thermal expansion (NTE) behavior of the nitrides. Our results also hint that direct ab initio MD simulations are a more elaborate method to investigate thermal expansion behavior of 2D materials than the QHA. Nevertheless, giant NTE coefficients are found for h-GaN and h-AlN within the covered temperature range 100-600 K regardless of the chosen computational method. This unusual NTE of 2D nitrides is reasoned with the out-of-plane oscillations related to the rippling behavior of the monolayers. | ||||
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| Language | Wos | 000620346100007 | Publication Date | 2021-02-22 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | Open Access | OpenAccess | |
| Notes | Approved |
Most recent IF: 3.836 | |||
| Call Number | UA @ admin @ c:irua:176671 | Serial | 7956 | ||
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| Author | Chaves, A.; Sousa, G.O.; Khaliji, K.; da Costa, D.R.; Farias, G.A.; Low, T. | ||||
| Title | Signatures of subband excitons in few-layer black phosphorus | Type | A1 Journal article | ||
| Year | 2021 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 103 | Issue | 16 | Pages | 165428 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Recent experimental measurements of light absorption in few-layer black phosphorus (BP) revealed a series of high and sharp peaks, interspersed by pairs of lower and broader features. Here, we propose a theoretical model for these excitonic states in few-layer BP within a continuum approach for the in-plane degrees of freedom and a tight-binding approximation that accounts for interlayer couplings. This yields excitonic transitions between different combinations of the subbands created by the coupled BP layers, which leads to a series of high and low oscillator strength excitonic states, consistent with the experimentally observed bright and dark exciton peaks, respectively. The main characteristics of such subband exciton states, as well as the possibility to control their energies and oscillator strengths via applied electric and magnetic fields, are discussed, towards a full understanding of the excitonic spectrum of few-layer BP and its tunability. | ||||
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| Language | Wos | 000647175200002 | Publication Date | 2021-04-28 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | Open Access | OpenAccess | |
| Notes | Approved |
Most recent IF: 3.836 | |||
| Call Number | UA @ admin @ c:irua:178384 | Serial | 8523 | ||
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| Author | Fomin, V.M.; Misko, V.R.; Devreese, J.T.; Moshchalkov, V.V. | ||||
| Title | Superconducting mesoscopic square loop | Type | A1 Journal article | ||
| Year | 1998 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 58 | Issue | Pages | 11703-11715 | |
| Keywords | A1 Journal article; Electron Microscopy for Materials Science (EMAT); | ||||
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| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000076716700093 | Publication Date | 2002-07-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0163-1829;1095-3795; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 43 | Open Access | |
| Notes | Approved |
Most recent IF: 3.836; 1998 IF: NA | |||
| Call Number | UA @ lucian @ c:irua:21906 | Serial | 3354 | ||
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| Author | Shields, P.A.; Nicholas, R.J.; Peeters, F.M.; Beaumont, B.; Gibart, P. | ||||
| Title | Free-carrier effects in gallium nitride epilayers: Valence-band dispersion | Type | A1 Journal article | ||
| Year | 2001 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 64 | Issue | 8 | Pages | 155303 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | The dispersion of the A-valence-band in GaN has been deduced from the observation of high-index magnetoexcitonic states in polarized interband magnetoreflectivity and is found to be strongly nonparabolic with a mass in the range 1.2-1.8m(e). It matches the theory of Kim et al. [Phys. Rev. B 56, 7363 (1997)] extremely well, which also gives a strong k-dependent A-valence-band mass. A strong phonon coupling leads to quenching of the observed transitions at about an LO-phonon energy above the band gap and a strong nonparabolicity. The valence band was deduced from subtracting from the reduced dispersion the electron contribution with a model that includes a full treatment of the electron-phonon interaction. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000170623000005 | Publication Date | 2002-07-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0163-1829;1095-3795; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 13 | Open Access | |
| Notes | Approved |
Most recent IF: 3.836; 2001 IF: NA | |||
| Call Number | UA @ lucian @ c:irua:37288 | Serial | 1274 | ||
| Permanent link to this record | |||||
| Author | Misko, V.R.; Fomin, V.M.; Devreese, J.T. | ||||
| Title | Strong enhancement of superconductivity in a nanosized Pb bridge | Type | A1 Journal article | ||
| Year | 2001 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 64 | Issue | Pages | 014517,1-13 | |
| Keywords | A1 Journal article; Electron Microscopy for Materials Science (EMAT); | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000169711900093 | Publication Date | 2002-07-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0163-1829;1095-3795; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 28 | Open Access | |
| Notes | Approved |
Most recent IF: 3.836; 2001 IF: NA | |||
| Call Number | UA @ lucian @ c:irua:34316 | Serial | 3181 | ||
| Permanent link to this record | |||||
| Author | Wang, Y.J.; Leem, Y.A.; McCombe, B.D.; Wu, X.G.; Peeters, F.M.; Jones, E.D.; Reno, J.R.; Lee, X.Y.; Jiang, H.W. | ||||
| Title | Strong three-level resonant magnetopolaron effect due to the intersubband coupling in heavily modulation-doped GaAs/AlxGa1-xAs single quantum wells at high magnetic-fields | Type | A1 Journal article | ||
| Year | 2001 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 64 | Issue | 16 | Pages | 161303 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Electron cyclotron resonance CR) measurements have been carried out in magnetic fields up to 32 T to study electron-phonon interaction in two heavily modulation-delta -doped GaAs/Al0.3Ga0.7As single-quantum-well samples. No measurable resonant magnetopolaron effects were observed in either sample in the region of the GaAs longitudinal optical (LO) phonons. However, when the CR frequency is above LO phonon frequency, omega (LO)=E-LO/(h) over bar, at high magnetic fields (B>27 T), electron CR exhibits a strong avoided-level-crossing splitting for both samples at frequencies close to (omega (LO)+ (E-2-E-1)1 (h) over bar, where E-2, and E-1 are the energies of the bottoms of the second and the first subbands, respectively. The energy separation between the two branches is large with the minimum separation of 40 cm(-1) occurring at around 30.5 T. A detailed theoretical analysis, which includes a self-consistent calculation of the band structure and the effects of electron-phonon interaction on the CR, shows that this type of splitting is due to a three-level resonance between the second Landau level of the first electron subband and the lowest Landau level of the second subband plus one GaAs LO phonon. The absence of occupation effects in the final states and weak screening or this three-level process yields large energy separation even in the presence of high electron densities. Excellent agreement between the theory and the experimental results is obtained. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000171866400009 | Publication Date | 2002-07-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0163-1829;1095-3795; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 7 | Open Access | |
| Notes | Approved |
Most recent IF: 3.836; 2001 IF: NA | |||
| Call Number | UA @ lucian @ c:irua:37278 | Serial | 3184 | ||
| Permanent link to this record | |||||
| Author | Verberck, B.; Nikolaev, A.V.; Michel, K.H. | ||||
| Title | Theoretical model for the structural phase transition at the metal-insulator transition in polymerized KC60 | Type | A1 Journal article | ||
| Year | 2002 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 66 | Issue | 16 | Pages | 165425-165425,14 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | The recently discovered structural transition in polymerized KC60 at about 50 K results in a doubling of the unit cell volume and accompanies the metal-insulator transition. Here we show that the ((a) over right arrow+(c) over right arrow,(b) over right arrow,(a) over right arrow-(c) over right arrow) superstructure results from small orientational charge density waves along the polymer chains and concomitant displacements of the surrounding K+ ions. The effect is specific for the space group Pmnn of KC60 and is absent in RbC60 and CsC60 (space group I2/m). The mechanism is relevant for the metal-insulator transition. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000179286400135 | Publication Date | 2002-10-30 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0163-1829;1095-3795; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 10 | Open Access | |
| Notes | Approved |
Most recent IF: 3.836; 2002 IF: NA | |||
| Call Number | UA @ lucian @ c:irua:94907 | Serial | 3608 | ||
| Permanent link to this record | |||||
| Author | Leys, F.E.; March, N.H.; Lamoen, D. | ||||
| Title | High pressure limiting forms of the zero-temperature equations of state of Ta and Pu from relativistic Thomas-Fermi theory | Type | A1 Journal article | ||
| Year | 2003 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 67 | Issue | Pages | 064109 | |
| Keywords | A1 Journal article; Electron Microscopy for Materials Science (EMAT); | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000181501100021 | Publication Date | 2003-03-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0163-1829;1095-3795; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 1 | Open Access | |
| Notes | Approved |
Most recent IF: 3.836; 2003 IF: NA | |||
| Call Number | UA @ lucian @ c:irua:45628 | Serial | 1439 | ||
| Permanent link to this record | |||||
| Author | Leys, F.E.; March, N.H.; Angilella, G.G.N.; Lamoen, D. | ||||
| Title | Self consistent nonlocal linear-response theory of a relativistic electron gas | Type | A1 Journal article | ||
| Year | 2003 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 67 | Issue | Pages | 113105 | |
| Keywords | A1 Journal article; Electron Microscopy for Materials Science (EMAT); | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000182035100005 | Publication Date | 2003-04-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0163-1829;1095-3795; | ISBN | Additional Links | UA library record; WoS full record; | |
| Impact Factor | 3.836 | Times cited | Open Access | ||
| Notes | Approved |
Most recent IF: 3.836; 2003 IF: NA | |||
| Call Number | UA @ lucian @ c:irua:45627 | Serial | 2973 | ||
| Permanent link to this record | |||||
| Author | Rosenauer, A.; Schowalter, M.; Glas, F.; Lamoen, D. | ||||
| Title | First-principles calculations of 002 structure factors for electron scattering in strained InxGa1-xAs | Type | A1 Journal article | ||
| Year | 2005 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 72 | Issue | 8 | Pages | 1-10 |
| Keywords | A1 Journal article; Electron Microscopy for Materials Science (EMAT); | ||||
| Abstract | This work provides values of electron scattering 002 structure factors for InxGa1-xAs as a function of the In concentration x=0 to 1. These results allow accurate compositional analysis of pseudomorphically grown InxGa1-xAs/GaAs layers by transmission electron microscopy methods relying on the chemical sensitivity of the (002) beam. The calculations go beyond the limits of the isolated atom approximation, because they take into account charge redistribution effects between atomic sites in the crystal, strain, and static atomic displacements. The computations were performed by the full potential linearized augmented plane-wave method using a generalized gradient approximation for the exchange and correlation part of the potential. The calculations of strained InxGa1-xAs correspond to the strain state in specimens with large, small, and intermediate thickness in the electron beam direction. Additionally, the effect of static atomic displacements is taken into account. All results are listed in a parameterized form. The calculated 002 structure factor vanishes at an In concentration of 16.4%. This value is in a good agreement with previously reported experimental measurements. Hence, our results are a significant improvement with respect to the isolated atom approximation which is conventionally applied in transmission electron microscopy simulations, and which predicts a value of 22.5%. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000231564600106 | Publication Date | 2005-08-12 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 42 | Open Access | |
| Notes | Approved |
Most recent IF: 3.836; 2005 IF: 3.185 | |||
| Call Number | UA @ lucian @ c:irua:54918 | Serial | 1201 | ||
| Permanent link to this record | |||||
| Author | Covaci, L.; Marsiglio, F. | ||||
| Title | Proximity effect and Josephson current in clean strong/weak/strong superconducting trilayers | Type | A1 Journal article | ||
| Year | 2006 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 73 | Issue | 1 | Pages | 014503 |
| Keywords | A1 Journal article | ||||
| Abstract | Recent measurements of the Josephson critical current through LSCO/LCO/LSCO thin films showed an unusually large proximity effect. Using the Bogoliubov-de Gennes equations for a tight-binding Hamiltonian we describe the proximity effect in weak links between a superconductor with critical temperature T-c and one with critical temperature T-c('), where T-c > T-c('). The weak link (N-') is therefore a superconductor above its own critical temperature and the superconducting regions are considered to have either s-wave or d-wave symmetry. We note that the proximity effect is enhanced due to the presence of superconducting correlations in the weak link. The dc Josephson current is calculated, and we obtain a nonzero value for temperatures greater than T-c(') for sizes of the weak links that can be almost an order of magnitude greater than the conventional coherence length. Considering pockets of superconductivity in the N-' layer, we show that this can lead to an even larger effect on the Josephson critical current by effectively shortening the weak link. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000235009000103 | Publication Date | 2006-01-03 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121 | ISBN | Additional Links | ||
| Impact Factor | 3.836 | Times cited | 31 | Open Access | |
| Notes | Approved |
Most recent IF: 3.836; 2006 IF: 3.107 | |||
| Call Number | UA @ lucian @ | Serial | 4427 | ||
| Permanent link to this record | |||||
| Author | Kim, W.; Covaci, L.; Marsiglio, F. | ||||
| Title | Impurity scattering of wave packets on a lattice | Type | A1 Journal article | ||
| Year | 2006 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 74 | Issue | 20 | Pages | 205120 |
| Keywords | A1 Journal article | ||||
| Abstract | Quantum transport in a lattice is distinct from its counterpart in continuum media. Even a free wave packet travels differently in a lattice than in the continuum. We describe quantum scattering in a one-dimensional lattice and illustrate characteristics of quantum transport such as resonant transmission. In particular we examine the transport characteristics of a random trimer model. We demonstrate the real-time propagation of a wave packet and its phase shift due to impurity configurations. Spin-flip scattering is also taken into account in a spin-chain system. We show how individual spins in the chain evolve as a result of a spin-flip interaction between an incoming electron and a spin chain. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000242409400030 | Publication Date | 2006-11-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121 | ISBN | Additional Links | ||
| Impact Factor | 3.836 | Times cited | 14 | Open Access | |
| Notes | Approved |
Most recent IF: 3.836; 2006 IF: 3.107 | |||
| Call Number | UA @ lucian @ | Serial | 4428 | ||
| Permanent link to this record | |||||
| Author | Kim, W.; Covaci, L.; Marsiglio, F. | ||||
| Title | Hidden symmetries of electronic transport in a disordered one-dimensional lattice | Type | A1 Journal article | ||
| Year | 2006 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 73 | Issue | 19 | Pages | 195109 |
| Keywords | A1 Journal article | ||||
| Abstract | Correlated, or extended, impurities play an important role in the transport properties of dirty metals. Here, we examine, in the framework of a tight-binding lattice, the transmission of a single electron through an array of correlated impurities. In particular we show that particles transmit through an impurity array in identical fashion, regardless of the direction of traversal. The demonstration of this fact is straightforward in the continuum limit, but requires a detailed proof for the discrete lattice. We also briefly demonstrate and discuss the time evolution of these scattering states, to delineate regions (in time and space) where the aforementioned symmetry is violated. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000237950400042 | Publication Date | 2006-05-11 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121 | ISBN | Additional Links | ||
| Impact Factor | 3.836 | Times cited | 5 | Open Access | |
| Notes | Approved |
Most recent IF: 3.836; 2006 IF: 3.107 | |||
| Call Number | UA @ lucian @ | Serial | 4429 | ||
| Permanent link to this record | |||||
| Author | Nogaret, A.; Lambert, N.J.; Peeters, F.M. | ||||
| Title | Electrically induced spin resonance fluorescence : 2 : fluorescence spectra | Type | A1 Journal article | ||
| Year | 2007 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 76 | Issue | 7 | Pages | |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | We model the fluorescence spectra of planar spin oscillators to find conditions that maximize spin resonance fluorescence. Spin oscillators perform Rabi oscillations under the effect of a periodic effective magnetic field caused by the winding motion of an electron in a gradient of magnetic field. We show that, despite the weak coupling of the spin magnetic dipole to the vacuum, spin oscillators excited by a direct current output a few nanowatts of microwave power, which is comparable to the best microwave sources. The large quantum efficiency relies on the combination of two effects. On the one hand, the spontaneous emission rate is enhanced by the synchronization of spin oscillators, which interact through the microwave field that they emit. On the other hand, the huge Rabi frequencies experienced by spin oscillators promote spins into upper levels of Zeeman transitions, from which a radiative cascade is triggered. We demonstrate different regimes of fluorescence which correspond to different values of the Rabi period relative to the spontaneous decay time and to the oscillator dwell time in the gradient of magnetic field. We investigate the device parameters which make these regimes experimentally accessible and find conditions that optimize microwave output. We find that microwave emission is centered around the cutoff frequency of spin oscillators. This has the advantage that the peak emission frequency may be tuned from zero continuously up to a few hundred gigahertz using an electrostatic gate. Quite remarkably for a spintronics effect, electrically induced spin resonance fluorescence does not require the injection of a spin polarized current. In fact, we show that microwave spectra are mostly independent of the incoming spin polarization except for magnetic waveguides which are shorter than a certain critical length, which we will specify. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000249155300092 | Publication Date | 2007-08-09 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 8 | Open Access | |
| Notes | Approved |
Most recent IF: 3.836; 2007 IF: 3.172 | |||
| Call Number | UA @ lucian @ c:irua:66118 | Serial | 898 | ||
| Permanent link to this record | |||||
| Author | Doğan, F.; Covaci, L.; Kim, W.; Marsiglio, F. | ||||
| Title | Emerging nonequilibrium bound state in spin-current–local-spin scattering | Type | A1 Journal article | ||
| Year | 2009 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 80 | Issue | 10 | Pages | 104434 |
| Keywords | A1 Journal article | ||||
| Abstract | Magnetization reversal is a well-studied problem with obvious applicability in computer hard drives. One can accomplish a magnetization reversal in at least one of two ways: application of a magnetic field or through a spin current. The latter is more amenable to a fully quantum-mechanical analysis. We formulate and solve the problem whereby a spin current interacts with a ferromagnetic Heisenberg spin chain, to eventually reverse the magnetization of the chain. Spin flips are accomplished through both elastic and inelastic scattering. A consequence of the inelastic-scattering channel, when it is no longer energetically possible, is the occurrence of a nonequilibrium bound state, which is an emergent property of the coupled local plus itinerant spin system. For certain definite parameter values the itinerant spin lingers near the local spins for some time, before eventually leaking out as an outwardly diffusing state. This phenomenon results in spin-flip dynamics and filtering properties for this type of system. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000270383100077 | Publication Date | 2009-09-25 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121 | ISBN | Additional Links | ||
| Impact Factor | 3.836 | Times cited | Open Access | ||
| Notes | Approved |
Most recent IF: 3.836; 2009 IF: 3.475 | |||
| Call Number | UA @ lucian @ | Serial | 4436 | ||
| Permanent link to this record | |||||
| Author | Singh, S.K.; Neek-Amal, M.; Costamagna, S.; Peeters, F.M. | ||||
| Title | Rippling, buckling, and melting of single- and multilayer MoS2 | Type | A1 Journal article | ||
| Year | 2015 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 91 | Issue | 91 | Pages | 014101 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Large-scale atomistic simulations using the reactive empirical bond order force field approach is implemented to investigate thermal and mechanical properties of single-layer (SL) and multilayer (ML) molybdenum disulfide (MoS2). The amplitude of the intrinsic ripples of SL MoS2 are found to be smaller than those exhibited by graphene (GE). Furthermore, because of the van der Waals interaction between layers, the out-of-plane thermal fluctuations of ML MoS2 decreases rapidly with increasing number of layers. This trend is confirmed by the buckling transition due to uniaxial stress which occurs for a significantly larger applied tension as compared to graphene. For SL MoS2, the melting temperature is estimated to be 3700 K which occurs through dimerization followed by the formation of small molecules consisting of two to five atoms. When different types of vacancies are inserted in the SL MoS2 it results in a decrease of both the melting temperature as well as the stiffness. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000347921300001 | Publication Date | 2015-01-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 40 | Open Access | |
| Notes | ; This work is supported by the ESF-Eurographene project CONGRAN, the Flemish Science Foundation (FWO-VI), and the Methusalem Foundation of the Flemish Government. We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. We would like to thanks Prof. Douglas E. Spearot [26] for giving us the implemented parameters of Mo-S in LAMMPS. ; | Approved |
Most recent IF: 3.836; 2015 IF: 3.736 | ||
| Call Number | c:irua:123834 | Serial | 2909 | ||
| Permanent link to this record | |||||
| Author | N. Gauquelin, E. Benckiser, M. K. Kinyanjui, M. Wu, Y. Lu, G. Christiani, G. Logvenov, H.-U. Habermeier, U. Kaiser, B. Keimer, and G. A. Botton | ||||
| Title | Atomically resolved EELS mapping of the interfacial structure of epitaxially strained LaNiO3/LaAlO3 superlattices | Type | A1 Journal Article | ||
| Year | 2014 | Publication | Physical Review B | Abbreviated Journal | |
| Volume | 90 | Issue | Pages | 195140 | |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | The interfacial atomic structure of a metallic LaNiO3/LaAlO3 superlattice grown on a LaSrAlO4 substrate was investigated using a combination of atomically resolved electron energy loss spectroscopy (EELS) at the Al K, Al L2,3, Sr L2,3, Ni L2,3, La M4,5, and O K edges as well as hybridization mapping of selected features of the O K-edge fine structure.We observe an additional La1−xSrxAl1−yNiyO3 layer at the substrate-superlattice interface, possibly linked to diffusion of Al and Sr into the growing film or a surface reconstruction due to Sr segregation. The roughness of the LaNiO3/LaAlO3 interfaces is found to be on average around one pseudocubic unit cell. The O K-edge EELS spectra revealed reduced spectral weight of the prepeak derived from Ni-O hybridized states in the LaNiO3 layers. We rule out oxygen nonstoichiometry of the LaNiO3 layers and discuss changes in the Ni-O hybridization due to heterostructuring as possible origin. |
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000345467000003 | Publication Date | 2014-11-20 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Additional Links | |||
| Impact Factor | Times cited | 17 | Open Access | ||
| Notes | Approved |
Most recent IF: NA | |||
| Call Number | EMAT @ emat @ | Serial | 4544 | ||
| Permanent link to this record | |||||
| Author | Shi, J.M.; Koenraad, P.M.; van de Stadt, A.F.W.; Peeters, F.M.; Devreese, J.T.; Wolter, J.H. | ||||
| Title | Electronic structure of a Si \delta-doped layer in a GaAs/AlxGa1-xAs/GaAs quantum barrier | Type | A1 Journal article | ||
| Year | 1996 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 54 | Issue | 11 | Pages | 7996-8004 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems | ||||
| Abstract | We present a theoretical study of the electronic structure of a heavily Si delta-doped layer in a GaAs/AlxGa1-xAs/GaAs quantum barrier. In this class of structures the effect of DX centers on the electronic properties can be tuned by changing the AlxGa1-xAs barrier width and/or the Al concentration, which leads to a lowering of the DX level with respect to the Fermi energy without disturbing the wave functions much. A self-consistent approach is developed in which the effective confinement potential and the Fermi energy of the system, the energies, the wave functions, and the electron densities of the discrete subbands have been obtained as a function of both the material parameters of the samples and the experimental conditions. The effect of DX centers on such structures at nonzero temperature and under an external pressure is investigated for three different models: (1) the DX(nc)(0) model with no correlation effects, (2) the d(+)/DX(0) model, and (3) the d(+)/DX(-) model with inclusion of correlation effects. In the actual calculation, influences of the background accepters, the discontinuity of the effective mass of the electrons at the interfaces of the different materials, band nonparabolicity, and the exchange-correlation energy of the electrons have been taken into account. We have found that (1) introducing a quantum barrier into delta-doped GaAs makes it possible to control the energy gaps between different electronic; subbands; (2) the electron wave functions are mon spread out when the repellent effect of the barriers is increased as compared to those in delta-doped GaAs; (3) increasing the quantum-barrier height and/or the application of hydrostatic pressure are helpful to experimentally observe the effect of the DX centers through a decrease of the total free-electron density; and (4) the correlation effects of the charged impurities are important for the systems under study. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | A1996VL14500066 | Publication Date | 2002-07-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0163-1829;1095-3795; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.736 | Times cited | 11 | Open Access | |
| Notes | Approved |
no | |||
| Call Number | UA @ lucian @ c:irua:104388 | Serial | 1012 | ||
| Permanent link to this record | |||||
| Author | Nicholas, R.J.; Sasaki, S.; Miura, N.; Peeters, F.M.; Shi, J.M.; Hai, G.Q.; Devreese, J.T.; Lawless, M.J.; Ashenford, D.E.; Lunn, B. | ||||
| Title | Interband magnetooptical studies of resonant polaron coupling in CdTe/Cd1-xMnxTe quantum-wells | Type | A1 Journal article | ||
| Year | 1994 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 50 | Issue | 11 | Pages | 7596-7601 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems | ||||
| Abstract | Magnetoreflectivity measurements of the 1s and 2s exciton energies in a CdTe/Cd1-xMnxTe superlattice have been made in magnetic fields up to 45 T, showing the resonant polaron coupling of electrons to LO phonons. Strong reflectivity features are seen for both the 1s and 2s excitons, which show a strong field-dependent spin splitting due to the dilute magnetic barriers. At B-z=0, the 2s exciton feature is observed lying 18 meV above the Is state, and is shifted upward in energy by the magnetic fields. No resonant behavior occurs when the 2s state passes through the LO-phonon energy of 21 meV, but at higher fields of around 20 T, the resonances for both spin states (sigma(+/-)) of the 2s exciton broaden and show a strong anticrossing behavior. These experiments are shown to be in excellent agreement with a theoretical treatment which includes the resonant polaron coupling of the electrons alone. Both experiment and theory demonstrate an extremely strong resonant splitting of the 2s exciton states of approximately 11 meV, which is over 50% of the LO-phonon energy. The dominance of single-particle polaron coupling is attributed to the relative sizes of the polaron (35 Angstrom A) and the exciton (50 Angstrom A) radius. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | A1994PJ43700045 | Publication Date | 2002-07-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0163-1829;1095-3795; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.736 | Times cited | 10 | Open Access | |
| Notes | Approved |
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| Call Number | UA @ lucian @ c:irua:99837 | Serial | 1687 | ||
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