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	Author	Moors, K.; Sorée, B.; Magnus, W.
	Title	Validity criteria for Fermi's golden rule scattering rates applied to metallic nanowires			Type	A1 Journal article
	Year	2016	Publication	Journal of physics : condensed matter	Abbreviated Journal	J Phys-Condens Mat
	Volume	28	Issue	28	Pages	365302
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Fermi's golden rule underpins the investigation of mobile carriers propagating through various solids, being a standard tool to calculate their scattering rates. As such, it provides a perturbative estimate under the implicit assumption that the effect of the interaction Hamiltonian which causes the scattering events is sufficiently small. To check the validity of this assumption, we present a general framework to derive simple validity criteria in order to assess whether the scattering rates can be trusted for the system under consideration, given its statistical properties such as average size, electron density, impurity density et cetera. We derive concrete validity criteria for metallic nanowires with conduction electrons populating a single parabolic band subjected to different elastic scattering mechanisms: impurities, grain boundaries and surface roughness.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000380754400013	Publication Date	2016-07-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0953-8984	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.649	Times cited	2	Open Access
	Notes	; ;			Approved	Most recent IF: 2.649
	Call Number	UA @ lucian @ c:irua:135011			Serial	4274
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	Author	Vanherck, J.; Sorée, B.; Magnus, W.
	Title	Anisotropic bulk and planar Heisenberg ferromagnets in uniform, arbitrarily oriented magnetic fields			Type	A1 Journal article
	Year	2018	Publication	Journal of physics : condensed matter	Abbreviated Journal	J Phys-Condens Mat
	Volume	30	Issue	27	Pages	275801
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Today, further downscaling of mobile electronic devices poses serious problems, such as energy consumption and local heat dissipation. In this context, spin wave majority gates made of very thin ferromagnetic films may offer a viable alternative. However, similar downscaling of magnetic thin films eventually enforces the latter to operate as quasi-2D magnets, the magnetic properties of which are not yet fully understood, especially those related to anisotropies and external magnetic fields in arbitrary directions. To this end, we have investigated the behaviour of an easy-plane and easy-axis anisotropic ferromagnet-both in two and three dimensions-subjected to a uniform magnetic field, applied along an arbitrary direction. In this paper, a spin-1/2 Heisenberg Hamiltonian with anisotropic exchange interactions is solved using double-time temperature-dependent Green's functions and the Tyablikov decoupling approximation. We determine various magnetic properties such as the Curie temperature and the magnetization as a function of temperature and the applied magnetic field, discussing the impact of the system's dimensionality and the type of anisotropy. The magnetic reorientation transition taking place in anisotropic Heisenberg ferromagnets is studied in detail. Importantly, spontaneous magnetization is found to be absent for easy-plane 2D spin systems with short range interactions.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000434980600001	Publication Date	2018-05-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0953-8984	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.649	Times cited		Open Access
	Notes	; ;			Approved	Most recent IF: 2.649
	Call Number	UA @ lucian @ c:irua:151945UA @ admin @ c:irua:151945			Serial	5012
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	Author	Slachmuylders, A.F.; Partoens, B.; Magnus, W.; Peeters, F.M.
	Title	Dielectric mismatch effect on the exciton states in cylindrical nanowires			Type	A1 Journal article
	Year	2006	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	74	Issue	23	Pages	235321,1-8
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000243195700080	Publication Date	2006-12-20
	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	39	Open Access
	Notes				Approved	Most recent IF: 3.836; 2006 IF: 3.107
	Call Number	UA @ lucian @ c:irua:62178			Serial	693
Permanent link to this record



	Author	Sorée, B.; Magnus, W.; Vandenberghe, W.
	Title	Low-field mobility in ultrathin silicon nanowire junctionless transistors			Type	A1 Journal article
	Year	2011	Publication	Applied physics letters	Abbreviated Journal	Appl Phys Lett
	Volume	99	Issue	23	Pages	233509-233509,3
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We theoretically investigate the phonon, surface roughness and ionized impurity limited low-field mobility of ultrathin silicon n-type nanowire junctionless transistors in the long channel approximation with wire radii ranging from 2 to 5 nm, as function of gate voltage. We show that surface roughness scattering is negligible as long as the wire radius is not too small and ionized impurity scattering is the dominant scattering mechanism. We also show that there exists an optimal radius where the ionized impurity limited mobility exhibits a maximum.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000298006100095	Publication Date	2011-12-09
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-6951;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.411	Times cited	20	Open Access
	Notes	; This work is supported by the EU project SQWIRE (FP7-ICT-STREP nr. 257111). William Vandenberghe gratefully acknowledges the Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). ;			Approved	Most recent IF: 3.411; 2011 IF: 3.844
	Call Number	UA @ lucian @ c:irua:92865			Serial	1850
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	Author	Van de Put, M.L.; Vandenberghe, W.G.; Sorée, B.; Magnus, W.; Fischetti, M.V.
	Title	Inter-ribbon tunneling in graphene: An atomistic Bardeen approach			Type	A1 Journal article
	Year	2016	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	119	Issue	119	Pages	214306
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	A weakly coupled system of two crossed graphene nanoribbons exhibits direct tunneling due to the overlap of the wavefunctions of both ribbons. We apply the Bardeen transfer Hamiltonian formalism, using atomistic band structure calculations to account for the effect of the atomic structure on the tunneling process. The strong quantum-size confinement of the nanoribbons is mirrored by the one-dimensional character of the electronic structure, resulting in properties that differ significantly from the case of inter-layer tunneling, where tunneling occurs between bulk two-dimensional graphene sheets. The current-voltage characteristics of the inter-ribbon tunneling structures exhibit resonance, as well as stepwise increases in current. Both features are caused by the energetic alignment of one-dimensional peaks in the density-of-states of the ribbons. Resonant tunneling occurs if the sign of the curvature of the coupled energy bands is equal, whereas a step-like increase in the current occurs if the signs are opposite. Changing the doping modulates the onset-voltage of the effects as well as their magnitude. Doping through electrostatic gating makes these structures promising for application towards steep slope switching devices. Using the atomistic empirical pseudopotentials based Bardeen transfer Hamiltonian method, inter-ribbon tunneling can be studied for the whole range of two-dimensional materials, such as transition metal dichalcogenides. The effects of resonance and of step-like increases in the current we observe in graphene ribbons are also expected in ribbons made from these alternative two-dimensional materials, because these effects are manifestations of the one-dimensional character of the density-of-states. Published by AIP Publishing.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000378923100022	Publication Date	2016-06-07
	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	6	Open Access
	Notes	; ;			Approved	Most recent IF: 2.068
	Call Number	UA @ lucian @ c:irua:134652			Serial	4198
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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.
	Address
	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
Permanent link to this record



	Author	Vandenberghe, W.G.; Verhulst, A.S.; Kao, K.-H.; De Meyer, K.; Sorée, B.; Magnus, W.; Groeseneken, G.
	Title	A model determining optimal doping concentration and material's band gap of tunnel field-effect transistors			Type	A1 Journal article
	Year	2012	Publication	Applied physics letters	Abbreviated Journal	Appl Phys Lett
	Volume	100	Issue	19	Pages	193509-193509,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We develop a model for the tunnel field-effect transistor (TFET) based on the Wentzel-Kramer-Brillouin approximation which improves over existing semi-classical models employing generation rates. We hereby introduce the concept of a characteristic tunneling length in direct semiconductors. Based on the model, we show that a limited density of states results in an optimal doping concentration as well as an optimal material's band gap to obtain the highest TFET on-current at a given supply voltage. The observed optimal-doping trend is confirmed by 2-dimensional quantum-mechanical simulations for silicon and germanium. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4714544]
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000304108000098	Publication Date	2012-05-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-6951;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.411	Times cited	25	Open Access
	Notes	; William Vandenberghe gratefully acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). This work was supported by IMEC's Industrial Affiliation Program. ;			Approved	Most recent IF: 3.411; 2012 IF: 3.794
	Call Number	UA @ lucian @ c:irua:98948			Serial	2105
Permanent link to this record



	Author	Compemolle, S.; Pourtois, G.; Sorée, B.; Magnus, W.; Chibotaru, L.F.; Ceulemans, A.
	Title	Conductance of a copper-nanotube bundle interface: impact of interface geometry and wave-function interference			Type	A1 Journal article
	Year	2008	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	77	Issue	19	Pages	193406,1-4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000256971600032	Publication Date	2008-05-20
	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; 2008 IF: 3.322
	Call Number	UA @ lucian @ c:irua:70215			Serial	479
Permanent link to this record



	Author	Carrillo-Nuñez, H.; Magnus, W.; Vandenberghe, W.G.; Sorée, B.; Peeters, F.M.
	Title	Phonon-assisted Zener tunneling in a cylindrical nanowire transistor			Type	A1 Journal article
	Year	2013	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	113	Issue	18	Pages	184507-184508
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The tunneling current has been computed for a cylindrical nanowire tunneling field-effect transistor (TFET) with an all-round gate that covers the source region. Being the underlying mechanism, band-to-band tunneling, mediated by electron-phonon interaction, is pronouncedly affected by carrier confinement in the radial direction and, therefore, involves the self-consistent solution of the Schrodinger and Poisson equations. The latter has been accomplished by exploiting a non-linear variational principle within the framework of the modified local density approximation taking into account the nonparabolicity of both the valence band and conduction band in relatively thick wires. Moreover, while the effective-mass approximation might still provide a reasonable description of the conduction band in relatively thick wires, we have found that the nonparabolicity of the valence band needs to be included. As a major conclusion, it is observed that confinement effects in nanowire tunneling field-effect transistors have a stronger impact on the onset voltage of the tunneling current in comparison with planar TFETs. On the other hand, the value of the onset voltage is found to be overestimated when the valence band nonparabolicity is ignored. (C) 2013 AIP Publishing LLC.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000319294100093	Publication Date	2013-05-10
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	4	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-VI), and the Interuniversity Attraction Poles, Belgium State, Belgium Science Policy, and IMEC. ;			Approved	Most recent IF: 2.068; 2013 IF: 2.185
	Call Number	UA @ lucian @ c:irua:109651			Serial	2599
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	Author	Vandenberghe, W.G.; Sorée, B.; Magnus, W.; Groeseneken, G.; Fischetti, M.V.
	Title	Impact of field-induced quantum confinement in tunneling field-effect devices			Type	A1 Journal article
	Year	2011	Publication	Applied physics letters	Abbreviated Journal	Appl Phys Lett
	Volume	98	Issue	14	Pages	143503,1-143503,3
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Being the working principle of a tunnel field-effect transistor, band-to-band tunneling is given a rigorous quantum mechanical treatment to incorporate confinement effects, multiple electron and hole valleys, and interactions with phonons. The model reveals that the strong band bending near the gate dielectric, required to create short tunnel paths, results in quantization of the energy bands. Comparison with semiclassical models reveals a big shift in the onset of tunneling. The effective mass difference of the distinct valleys is found to reduce the subthreshold swing steepness.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000289297800074	Publication Date	2011-04-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-6951;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.411	Times cited	76	Open Access
	Notes	; The authors acknowledge Anne Verhulst for useful discussions. William Vandenberghe gratefully acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). This work was supported by IMEC's Industrial Affiliation Program. ;			Approved	Most recent IF: 3.411; 2011 IF: 3.844
	Call Number	UA @ lucian @ c:irua:89297			Serial	1559
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	Author	Verreck, D.; Verhulst, A.S.; Van de Put, M.; Sorée, B.; Magnus, W.; Mocuta, A.; Collaert, N.; Thean, A.; Groeseneken, G.
	Title	Full-zone spectral envelope function formalism for the optimization of line and point tunnel field-effect transistors			Type	A1 Journal article
	Year	2015	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	118	Issue	118	Pages	134502
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Efficient quantum mechanical simulation of tunnel field-effect transistors (TFETs) is indispensable to allow for an optimal configuration identification. We therefore present a full-zone 15-band quantum mechanical solver based on the envelope function formalism and employing a spectral method to reduce computational complexity and handle spurious solutions. We demonstrate the versatility of the solver by simulating a 40 nm wide In0.53Ga0.47As lineTFET and comparing it to p-n-i-n configurations with various pocket and body thicknesses. We find that the lineTFET performance is not degraded compared to semi-classical simulations. Furthermore, we show that a suitably optimized p-n-i-n TFET can obtain similar performance to the lineTFET. (C) 2015 AIP Publishing LLC.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000362668400025	Publication Date	2015-10-01
	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	; D. Verreck acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). This work was supported by imec's Industrial Affiliation Program. ;			Approved	Most recent IF: 2.068; 2015 IF: 2.183
	Call Number	UA @ lucian @ c:irua:128765			Serial	4183
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	Author	Kenawy, A.; Magnus, W.; Milošević, M.V.; Sorée, B.
	Title	Voltage-controlled superconducting magnetic memory			Type	A1 Journal article
	Year	2019	Publication	AIP advances T2 – 64th Annual Conference on Magnetism and Magnetic Materials (MMM), NOV 04-08, 2019, Las Vegas, NV	Abbreviated Journal
	Volume	9	Issue	12	Pages	125223
	Keywords	A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
	Abstract	Over the past few decades, superconducting circuits have been used to realize various novel electronic devices such as quantum bits, SQUIDs, parametric amplifiers, etc. One domain, however, where superconducting circuits fall short is information storage. Superconducting memories are based on the quantization of magnetic flux in superconducting loops. Standard implementations store information as magnetic flux quanta in a superconducting loop interrupted by two Josephson junctions (i.e., a SQUID). However, due to the large inductance required, the size of the SQUID loop cannot be scaled below several micrometers, resulting in low-density memory chips. Here, we propose a scalable memory consisting of a voltage-biased superconducting ring threaded by a half-quantum flux bias. By numerically solving the time-dependent Ginzburg-Landau equations, we show that applying a time-dependent bias voltage in the microwave range constitutes a writing mechanism to change the number of stored flux quanta within the ring. Since the proposed device does not require a large loop inductance, it can be scaled down, enabling a high-density memory technology. (C) 2019 Author(s).
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000515525300002	Publication Date	2019-12-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2158-3226	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:167551			Serial	8740
Permanent link to this record



	Author	Kenawy, A.; Magnus, W.; Milošević, M.V.; Sorée, B.
	Title	Electronically tunable quantum phase slips in voltage-biased superconducting rings as a base for phase-slip flux qubits			Type	A1 Journal article
	Year	2020	Publication	Superconductor Science & Technology	Abbreviated Journal	Supercond Sci Tech
	Volume	33	Issue	12	Pages	125002
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Quantum phase slips represent a coherent mechanism to couple flux states of a superconducting loop. Since their first direct observation, there have been substantial developments in building charge-insensitive quantum phase-slip circuits. At the heart of these devices is a weak link, often a nanowire, interrupting a superconducting loop. Owing to the very small cross-sectional area of such a nanowire, quantum phase slip rates in the gigahertz range can be achieved. Instead, here we present the use of a bias voltage across a superconducting loop to electrostatically induce a weak link, thereby amplifying the rate of quantum phase slips without physically interrupting the loop. Our simulations reveal that the bias voltage modulates the free energy barrier between subsequent flux states in a very controllable fashion, providing a route towards a phase-slip flux qubit with a broadly tunable transition frequency.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000577207000001	Publication Date	2020-09-16
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0953-2048	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.6	Times cited	4	Open Access
	Notes	; ;			Approved	Most recent IF: 3.6; 2020 IF: 2.878
	Call Number	UA @ admin @ c:irua:172643			Serial	6503
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	Author	Vandenberghe, W.; Sorée, B.; Magnus, W.; Fischetti, M.V.
	Title	Generalized phonon-assisted Zener tunneling in indirect semiconductors with non-uniform electric fields : a rigorous approach			Type	A1 Journal article
	Year	2011	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	109	Issue	12	Pages	124503-124503,12
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	A general framework to calculate the Zener current in an indirect semiconductor with an externally applied potential is provided. Assuming a parabolic valence and conduction band dispersion, the semiconductor is in equilibrium in the presence of the external field as long as the electron-phonon interaction is absent. The linear response to the electron-phonon interaction results in a non-equilibrium system. The Zener tunneling current is calculated from the number of electrons making the transition from valence to conduction band per unit time. A convenient expression based on the single particle spectral functions is provided, enabling the evaluation of the Zener tunneling current under any three-dimensional potential profile. For a one-dimensional potential profile an analytical expression is obtained for the current in a bulk semiconductor, a semiconductor under uniform field, and a semiconductor under a non-uniform field using the WKB (Wentzel-Kramers-Brillouin) approximation. The obtained results agree with the Kane result in the low field limit. A numerical example for abrupt p-n diodes with different doping concentrations is given, from which it can be seen that the uniform field model is a better approximation than the WKB model, but a direct numerical treatment is required for low bias conditions.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000292331200134	Publication Date	2011-06-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	41	Open Access
	Notes	; William Vandenberghe gratefully acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). ;			Approved	Most recent IF: 2.068; 2011 IF: 2.168
	Call Number	UA @ lucian @ c:irua:90808			Serial	1325
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	Author	Moors, K.; Sorée, B.; Magnus, W.
	Title	Modeling surface roughness scattering in metallic nanowires			Type	A1 Journal article
	Year	2015	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	118	Issue	118	Pages	124307
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Ando's model provides a rigorous quantum-mechanical framework for electron-surface roughness scattering, based on the detailed roughness structure. We apply this method to metallic nanowires and improve the model introducing surface roughness distribution functions on a finite domain with analytical expressions for the average surface roughness matrix elements. This approach is valid for any roughness size and extends beyond the commonly used Prange-Nee approximation. The resistivity scaling is obtained from the self-consistent relaxation time solution of the Boltzmann transport equation and is compared to Prange-Nee's approach and other known methods. The results show that a substantial drop in resistivity can be obtained for certain diameters by achieving a large momentum gap between Fermi level states with positive and negative momentum in the transport direction. (C) 2015 AIP Publishing LLC.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000362565800032	Publication Date	2015-09-24
	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	; ;			Approved	Most recent IF: 2.068; 2015 IF: 2.183
	Call Number	UA @ lucian @ c:irua:129425			Serial	4207
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	Author	Li, B.; Slachmuylders, A.F.; Partoens, B.; Magnus, W.; Peeters, F.M.
	Title	Dielectric mismatch effect on shallow impurity states in a semiconductor nanowire			Type	A1 Journal article
	Year	2008	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	77	Issue		Pages	115335,1-10
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000254542800131	Publication Date	2008-03-19
	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	24	Open Access
	Notes				Approved	Most recent IF: 3.836; 2008 IF: 3.322
	Call Number	UA @ lucian @ c:irua:69630			Serial	692
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	Author	Pourghaderi, M.A.; Magnus, W.; Sorée, B.; Meuris, M.; de Meyer, K.; Heyns, M.
	Title	Tunneling-lifetime model for metal-oxide-semiconductor structures			Type	A1 Journal article
	Year	2009	Publication	Physical review : B : solid state	Abbreviated Journal	Phys Rev B
	Volume	80	Issue	8	Pages	085315,1-085315,10
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	In this paper we investigate the basic physics of charge carriers (electrons) leaking out of the inversion layer of a metal-oxide-semiconductor capacitor with a biased gate. In particular, we treat the gate leakage current as resulting from two combined processes: (1) the time-dependent decay of electron wave packets representing the inversion-layer charge and (2) the local generation of new electrons replacing those that have leaked away. As a result, the gate current simply emerges as the ratio of the total charge in the inversion layer to the tunneling lifetime. The latter is extracted from the quantum dynamics of the decaying wave packets, while the generation rate is incorporated as a phenomenological source term in the continuity equation. Not only do the gate currents calculated with this model agree very well with experiment, the model also provides an onset to solve the paradox of the current-free bound states representing the resonances of the Schrödinger equation that governs the fully coupled metal-oxide-semiconductor system.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000269639300076	Publication Date	2009-08-21
	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	2	Open Access
	Notes				Approved	Most recent IF: 3.836; 2009 IF: 3.475
	Call Number	UA @ lucian @ c:irua:78294			Serial	3763
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	Author	Li, B.; Partoens, B.; Peeters, F.M.; Magnus, W.
	Title	Dielectric mismatch effect on coupled shallow impurity states in a semiconductor nanowire			Type	A1 Journal article
	Year	2009	Publication	Physical review : B : solid state	Abbreviated Journal	Phys Rev B
	Volume	79	Issue	8	Pages	085306,1-085306,7
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Coupled shallow impurity states in a freestanding semiconductor nanowire and in a semiconductor nanowire surrounded by a metallic gate are studied within the effective-mass approximation. Bonding and antibonding states are found due to the coupling of the two impurities, and their energy converges with increasing distance di between the two impurities. The dependences of the binding energy on the wire radius R, the distance di between the two impurities, and the impurity radial position in the nanowire are examined.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000263816000051	Publication Date	2009-02-09
	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	11	Open Access
	Notes				Approved	Most recent IF: 3.836; 2009 IF: 3.475
	Call Number	UA @ lucian @ c:irua:76223			Serial	691
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	Author	Zhang, Y.; Fischetti, M.V.; Sorée, B.; Magnus, W.; Heyns, M.; Meuris, M.
	Title	Physical modeling of strain-dependent hole mobility in Ge p-channel inversion layers			Type	A1 Journal article
	Year	2009	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	106	Issue	8	Pages	083704,1-083704,9
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We present comprehensive calculations of the low-field hole mobility in Ge p-channel inversion layers with SiO2 insulator using a six-band k·p band-structure model. The cases of relaxed, biaxially, and uniaxially (both tensily and compressively) strained Ge are studied employing an efficient self-consistent methodmaking use of a nonuniform spatial mesh and of the Broyden second methodto solve the coupled envelope-wave function k·p and Poisson equations. The hole mobility is computed using the KuboGreenwood formalism accounting for nonpolar hole-phonon scattering and scattering with interfacial roughness. Different approximations to handle dielectric screening are also investigated. As our main result, we find a large enhancement (up to a factor of 10 with respect to Si) of the mobility in the case of uniaxial compressive stress similarly to the well-known case of Si. Comparison with experimental data shows overall qualitative agreement but with significant deviations due mainly to the unknown morphology of the rough Ge-insulator interface, to additional scattering with surface optical phonon from the high- insulator, to Coulomb scattering interface traps or oxide chargesignored in our calculationsand to different channel structures employed.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000271358100050	Publication Date	2009-10-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	29	Open Access
	Notes				Approved	Most recent IF: 2.068; 2009 IF: 2.072
	Call Number	UA @ lucian @ c:irua:80137			Serial	2617
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	Author	Slachmuylders, A.F.; Partoens, B.; Peeters, F.M.; Magnus, W.
	Title	Effect of a metallic gate on the energy levels of a shallow donor			Type	A1 Journal article
	Year	2008	Publication	Applied physics letters	Abbreviated Journal	Appl Phys Lett
	Volume	92	Issue	8	Pages	083104,1-3
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000254297300074	Publication Date	2008-02-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-6951;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.411	Times cited	14	Open Access
	Notes				Approved	Most recent IF: 3.411; 2008 IF: 3.726
	Call Number	UA @ lucian @ c:irua:69618			Serial	792
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	Author	Slachmuylders, A.F.; Partoens, B.; Magnus, W.; Peeters, F.M.
	Title	Trions in cylindrical nanowires with a dielectric mismatch			Type	A1 Journal article
	Year	2007	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	76	Issue	7	Pages	075405,1-9
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000249155300136	Publication Date	2007-08-07
	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	12	Open Access
	Notes				Approved	Most recent IF: 3.836; 2007 IF: 3.172
	Call Number	UA @ lucian @ c:irua:66119			Serial	3732
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	Author	Moors, K.; Sorée, B.; Tokei, Z.; Magnus, W.
	Title	Resistivity scaling and electron relaxation times in metallic nanowires			Type	A1 Journal article
	Year	2014	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	116	Issue	6	Pages	063714
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We study the resistivity scaling in nanometer-sized metallic wires due to surface roughness and grain-boundaries, currently the main cause of electron scattering in nanoscaled interconnects. The resistivity has been obtained with the Boltzmann transport equation, adopting the relaxation time approximation of the distribution function and the effective mass approximation for the conducting electrons. The relaxation times are calculated exactly, using Fermi's golden rule, resulting in a correct relaxation time for every sub-band state contributing to the transport. In general, the relaxation time strongly depends on the sub-band state, something that remained unclear with the methods of previous work. The resistivity scaling is obtained for different roughness and grain-boundary properties, showing large differences in scaling behavior and relaxation times. Our model clearly indicates that the resistivity is dominated by grain-boundary scattering, easily surpassing the surface roughness contribution by a factor of 10. (C) 2014 AIP Publishing LLC.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000341179400036	Publication Date	2014-08-15
	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	17	Open Access
	Notes	; ;			Approved	Most recent IF: 2.068; 2014 IF: 2.183
	Call Number	UA @ lucian @ c:irua:119260			Serial	2882
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	Author	Carrillo-Nuñez, H.; Magnus, W.; Peeters, F.M.
	Title	A simplified quantum mechanical model for nanowire transistors based on non-linear variational calculus			Type	A1 Journal article
	Year	2010	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	108	Issue	6	Pages	063708,1-063708,8
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	A simplified quantum mechanical model is developed to investigate quantum transport features such as the electron concentration and the current flowing through a silicon nanowire metal-oxide-semiconductor field-effect transistor (MOSFET). In particular, the electron concentration is extracted from a self-consistent solution of the Schrödinger and Poisson equations as well as the ballistic Boltzmann equation which have been solved by exploiting a nonlinear variational principle within the framework of the generalized local density approximation. A suitable action functional has been minimized and details of the implementation and its numerical minimization are given. The current density and its related current-voltage characteristics are calculated from the one-dimensional ballistic steady-state Boltzmann transport equation which is solved analytically by using the method of characteristic curves. The straightforward implementation, the computational speed and the good qualitative behavior of the transport characteristics observed in our approach make it a promising simulation method for modeling quantum transport in nanowire MOSFETs.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000282646400067	Publication Date	2010-09-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	7	Open Access
	Notes	; This work was supported by Flemish Science Foundation (FWO-VI) and the Interuniversity Attraction Poles, Belgium State, Belgium Science Policy, and IMEC. ;			Approved	Most recent IF: 2.068; 2010 IF: 2.079
	Call Number	UA @ lucian @ c:irua:84943			Serial	3006
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	Author	Vandenberghe, W.; Sorée, B.; Magnus, W.; Groeseneken, G.
	Title	Zener tunneling in semiconductors under nonuniform electric fields			Type	A1 Journal article
	Year	2010	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	107	Issue	5	Pages	054520,1-054520,7
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Recently, a renewed interest in Zener tunneling has arisen because of its increasing impact on semiconductor device performance at nanometer dimensions. In this paper we evaluate the tunnel probability under the action of a nonuniform electric field using a two-band model and arrive at significant deviations from the commonly used Kanes model, valid for weak uniform fields only. A threshold on the junction bias where Kanes model for Zener tunneling breaks down is determined. Comparison with Kanes model particularly shows that our calculation yields a higher tunnel probability for intermediate electric fields and a lower tunnel probability for high electric fields. When performing a current calculation comparing to the WKB approximation for the case of an abrupt p-n junction significant differences concerning the shape of the I-V curve are demonstrated.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000275657500136	Publication Date	2010-03-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	22	Open Access
	Notes	; William Vandenberghe gratefully acknowledges the support of a Ph. D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). These authors acknowledge the support from IMEC's Industrial Affiliation Program and the authors would like to thank Anne Verhulst for useful comments. ;			Approved	Most recent IF: 2.068; 2010 IF: 2.079
	Call Number	UA @ lucian @ c:irua:82450			Serial	3929
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	Author	Verreck, D.; Van de Put, M.; Sorée, B.; Verhulst, A.S.; Magnus, W.; Vandenberghe, W.G.; Collaert, N.; Thean, A.; Groeseneken, G.
	Title	Quantum mechanical solver for confined heterostructure tunnel field-effect transistors			Type	A1 Journal article
	Year	2014	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	115	Issue	5	Pages	053706-53708
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Heterostructure tunnel field-effect transistors (HTFET) are promising candidates for low-power applications in future technology nodes, as they are predicted to offer high on-currents, combined with a sub-60 mV/dec subthreshold swing. However, the effects of important quantum mechanical phenomena like size confinement at the heterojunction are not well understood, due to the theoretical and computational difficulties in modeling realistic heterostructures. We therefore present a ballistic quantum transport formalism, combining a novel envelope function approach for semiconductor heterostructures with the multiband quantum transmitting boundary method, which we extend to 2D potentials. We demonstrate an implementation of a 2-band version of the formalism and apply it to study confinement in realistic heterostructure diodes and p-n-i-n HTFETs. For the diodes, both transmission probabilities and current densities are found to decrease with stronger confinement. For the p-n-i-n HTFETs, the improved gate control is found to counteract the deterioration due to confinement. (C) 2014 AIP Publishing LLC.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000331645900040	Publication Date	2014-02-05
	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	15	Open Access
	Notes	; D. Verreck acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). This work was supported by imec's Industrial Affiliation Program. ;			Approved	Most recent IF: 2.068; 2014 IF: 2.183
	Call Number	UA @ lucian @ c:irua:115825			Serial	2780
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	Author	Pourghaderi, M.A.; Magnus, W.; Sorée, B.; Meuris, M.; de Meyer, K.; Heyns, M.
	Title	Ballistic current in metal-oxide-semiconductor field-effect transistors: the role of device topology			Type	A1 Journal article
	Year	2009	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	106	Issue	5	Pages	053702,1-053702,8
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	In this study we investigate the effect of device topology on the ballistic current in n-channel metal-oxide-semiconductor field-effect transistors. Comparison of the nanoscale planar and double-gate devices reveals that, down to a certain thickness of the double gate film, the ballistic current flowing in the double gate device is twice as large compared to its planar counterpart. On the other hand, further thinning of the film beyond this threshold is found to change noticeably the confinement and transport characteristics, which are strongly depending on the film material and the surface orientation. For double gate Ge and Si devices there exists a critical film thickness below which the transverse gate field is no longer effectively screened by the inversion layer electron gas and mutual inversion of the two gates is turned on. In the case of GaAs and other similar IIIV compounds, a decrease in the film thickness may drastically change the occupation of the L-valleys and therefore amend the transport properties. The simulation results show that, in both cases, the ballistic current and the transconductance are considerably enhanced.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000269850300052	Publication Date	2009-09-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;	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; 2009 IF: 2.072
	Call Number	UA @ lucian @ c:irua:79744			Serial	214
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	Author	Vanherck, J.; Bacaksiz, C.; Sorée, B.; Milošević, M.V.; Magnus, W.
	Title	2D ferromagnetism at finite temperatures under quantum scrutiny			Type	A1 Journal article
	Year	2020	Publication	Applied Physics Letters	Abbreviated Journal	Appl Phys Lett
	Volume	117	Issue	5	Pages	052401
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Recent years have seen a tremendous rise of two-dimensional (2D) magnetic materials, several of which were verified experimentally. However, most of the theoretical predictions to date rely on ab initio methods, at zero temperature and fluctuation-free, while one certainly expects detrimental quantum fluctuations at finite temperatures. Here, we present the solution of the quantum Heisenberg model for honeycomb/hexagonal lattices with anisotropic exchange interaction up to third nearest neighbors and in an applied field in arbitrary direction, which answers the question whether long-range magnetization can indeed survive in the ultrathin limit of materials, up to which temperature, and what the characteristic excitation (magnon) frequencies are, all essential to envisaged applications of magnetic 2D materials. We find that long-range magnetic order persists at finite temperature for materials with overall easy-axis anisotropy. We validate the calculations on the examples of monolayers CrI3, CrBr3, and MnSe2. Moreover, we provide an easy-to-use tool to calculate Curie temperatures of new 2D computational materials.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000559330100001	Publication Date	2020-08-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-6951; 1077-3118	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4	Times cited	8	Open Access
	Notes	; This work was supported by the Research Foundation-Flanders (FWO) and the special research funds of the University of Antwerp (BOF-UA). ;			Approved	Most recent IF: 4; 2020 IF: 3.411
	Call Number	UA @ admin @ c:irua:171176			Serial	6445
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	Author	Kao, K.-H.; Verhulst, A.S.; Van de Put, M.; Vandenberghe, W.G.; Sorée, B.; Magnus, W.; De Meyer, K.
	Title	Tensile strained Ge tunnel field-effect transistors: k\cdot p material modeling and numerical device simulation			Type	A1 Journal article
	Year	2014	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	115	Issue	4	Pages	044505-44508
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Group IV based tunnel field-effect transistors generally show lower on-current than III-V based devices because of the weaker phonon-assisted tunneling transitions in the group IV indirect bandgap materials. Direct tunneling in Ge, however, can be enhanced by strain engineering. In this work, we use a 30-band k.p method to calculate the band structure of biaxial tensile strained Ge and then extract the bandgaps and effective masses at Gamma and L symmetry points in k-space, from which the parameters for the direct and indirect band-to-band tunneling (BTBT) models are determined. While transitions from the heavy and light hole valence bands to the conduction band edge at the L point are always bridged by phonon scattering, we highlight a new finding that only the light-holelike valence band is strongly coupling to the conduction band at the Gamma point even in the presence of strain based on the 30-band k.p analysis. By utilizing a Technology Computer Aided Design simulator equipped with the calculated band-to-band tunneling BTBT models, the electrical characteristics of tensile strained Ge point and line tunneling devices are self-consistently computed considering multiple dynamic nonlocal tunnel paths. The influence of field-induced quantum confinement on the tunneling onset is included. Our simulation predicts that an on-current up to 160 (260) mu A/mu m can be achieved along with on/off ratio > 10(6) for V-DD = 0.5V by the n-type (p-type) line tunneling device made of 2.5% biaxial tensile strained Ge. (C) 2014 AIP Publishing LLC.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000331210800113	Publication Date	2014-01-26
	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	26	Open Access
	Notes	; Authors would like to thank Dr. Mohammad Ali Pourghaderi for useful discussions on the nonparabolicity. Authors would also like to thank Professor Eddy Simoen and Dr. Yosuke Shimura for useful discussions about the validity of modeled bandgaps and effective masses. This work was also supported by IMEC's Industrial Affiliation Program. ;			Approved	Most recent IF: 2.068; 2014 IF: 2.183
	Call Number	UA @ lucian @ c:irua:115800			Serial	3505
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	Author	De Clercq, M.; Moors, K.; Sankaran, K.; Pourtois, G.; Dutta, S.; Adelmann, C.; Magnus, W.; Sorée, B.
	Title	Resistivity scaling model for metals with conduction band anisotropy			Type	A1 Journal article
	Year	2018	Publication	Physical review materials	Abbreviated Journal
	Volume	2	Issue	3	Pages	033801
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	It is generally understood that the resistivity of metal thin films scales with film thickness mainly due to grain boundary and boundary surface scattering. Recently, several experiments and ab initio simulations have demonstrated the impact of crystal orientation on resistivity scaling. The crystal orientation cannot be captured by the commonly used resistivity scaling models and a qualitative understanding of its impact is currently lacking. In this work, we derive a resistivity scaling model that captures grain boundary and boundary surface scattering as well as the anisotropy of the band structure. The model is applied to Cu and Ru thin films, whose conduction bands are (quasi-) isotropic and anisotropic, respectively. After calibrating the anisotropy with ab initio simulations, the resistivity scaling models are compared to experimental resistivity data and a renormalization of the fitted grain boundary reflection coefficient can be identified for textured Ru.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	College Park, Md	Editor
	Language		Wos	000426787600001	Publication Date	2018-03-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2475-9953	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes	; The authors acknowledge the support by the Fonds National de la Recherche Luxembourg (ATTRACT Grant No. 7556175). ;			Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:149866UA @ admin @ c:irua:149866			Serial	4947
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	Author	Lujan, G.S.; Sorée, B.; Magnus, W.; de Meyer, K.
	Title	A method to calculate tunneling leakage currents in silicon inversion layers			Type	A1 Journal article
	Year	2006	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	100	Issue	3	Pages	033708,1-5
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000239764100051	Publication Date	2006-08-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	1	Open Access
	Notes				Approved	Most recent IF: 2.068; 2006 IF: 2.316
	Call Number	UA @ lucian @ c:irua:60963			Serial	2016
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