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	Author	Vanderveken, F.; Ahmad, H.; Heyns, M.; Sorée, B.; Adelmann, C.; Ciubotaru, F.
	Title	Excitation and propagation of spin waves in non-uniformly magnetized waveguides			Type	A1 Journal article
	Year	2020	Publication	Journal Of Physics D-Applied Physics	Abbreviated Journal	J Phys D Appl Phys
	Volume	53	Issue	49	Pages	495006
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The characteristics of spin waves in ferromagnetic waveguides with non-uniform magnetization have been investigated for situations where the shape anisotropy field of the waveguide is comparable to the external bias field. Spin-wave generation was realized by the magnetoelastic effect by applying normal and shear strain components, as well as by the Oersted field emitted by an inductive antenna. The magnetoelastic excitation field has a non-uniform profile over the width of the waveguide because of the non-uniform magnetization orientation, whereas the Oersted field remains uniform. Using micromagnetic simulations, we indicate that both types of excitation fields generate quantised width modes with both odd and even mode numbers as well as tilted phase fronts. We demonstrate that these effects originate from the average magnetization orientation with respect to the main axes of the magnetic waveguide. Furthermore, it is indicated that the excitation efficiency of the second-order mode generally surpasses that of the first-order mode due to their symmetry. The relative intensity of the excited modes can be controlled by the strain state as well as by tuning the dimensions of the excitation area. Finally, we demonstrate that the nonreciprocity of spin-wave radiation due to the chirality of an Oersted field generated by an inductive antenna is absent for magnetoelastic spin-wave excitation.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000575331600001	Publication Date	2020-08-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0022-3727	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.4	Times cited	1	Open Access
	Notes	; This work has been supported by imec's industrial affiliate program on beyond-CMOS logic. It has also received funding from the European Union's Horizon 2020 research and innovation program within the FET-OPEN project CHIRON under grant agreement No. 801055. F V acknowledges financial support from the Research Foundation -Flanders (FWO) through grant No. 1S05719N. ;			Approved	Most recent IF: 3.4; 2020 IF: 2.588
	Call Number	UA @ admin @ c:irua:172641			Serial	6515
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	Author	Osca, J.; Moors, K.; Sorée, B.; Serra, L.
	Title	Fabry-Perot interferometry with gate-tunable 3D topological insulator nanowires			Type	A1 Journal article
	Year	2021	Publication	Nanotechnology	Abbreviated Journal	Nanotechnology
	Volume	32	Issue	43	Pages	435002
	Keywords	A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
	Abstract	Three-dimensional topological insulator (3D TI) nanowires display remarkable magnetotransport properties that can be attributed to their spin-momentum-locked surface states such as quasiballistic transport and Aharonov-Bohm oscillations. Here, we focus on the transport properties of a 3D TI nanowire with a gated section that forms an electronic Fabry-Perot (FP) interferometer that can be tuned to act as a surface-state filter or energy barrier. By tuning the carrier density and length of the gated section of the wire, the interference pattern can be controlled and the nanowire can become fully transparent for certain topological surface-state input modes while completely filtering out others. We also consider the interplay of FP interference with an external magnetic field, with which Klein tunneling can be induced, and transverse asymmetry of the gated section, e.g. due to a top-gated structure, which displays an interesting analogy with Rashba nanowires. Due to its rich conductance phenomenology, we propose a 3D TI nanowire with gated section as an ideal setup for a detailed transport-based characterization of 3D TI nanowire surface states near the Dirac point, which could be useful towards realizing 3D TI nanowire-based topological superconductivity and Majorana bound states.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000682173800001	Publication Date	2021-07-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0957-4484	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.44	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 3.44
	Call Number	UA @ admin @ c:irua:180487			Serial	6990
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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	Mohammed, M.; Verhulst, A.S.; Verreck, D.; Van de Put, M.; Simoen, E.; Sorée, B.; Kaczer, B.; Degraeve, R.; Mocuta, A.; Collaert, N.; Thean, A.; Groeseneken, G.
	Title	Electric-field induced quantum broadening of the characteristic energy level of traps in semiconductors and oxides			Type	A1 Journal article
	Year	2016	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	120	Issue	120	Pages	245704
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The trap-assisted tunneling (TAT) current in tunnel field-effect transistors (TFETs) is one of the crucial factors degrading the sub-60 mV/dec sub-threshold swing. To correctly predict the TAT currents, an accurate description of the trap is required. Since electric fields in TFETs typically reach beyond 10(6) V/cm, there is a need to quantify the impact of such high field on the traps. We use a quantum mechanical implementation based on the modified transfer matrix method to obtain the trap energy level. We present the qualitative impact of electric field on different trap configurations, locations, and host materials, including both semiconductors and oxides. We determine that there is an electric-field related trap level shift and level broadening. We find that these electric-field induced quantum effects can enhance the trap emission rates. Published by AIP Publishing.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000392174000028	Publication Date	2016-12-26
	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	6	Open Access
	Notes	; This work was supported by imec's Industrial Affiliation Program. D. Verreck acknowledges the support of a PhD stipend from IWT-Vlaanderen. ;			Approved	Most recent IF: 2.068
	Call Number	UA @ lucian @ c:irua:141481			Serial	4593
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	Author	Verreck, D.; Verhulst, A.S.; Sorée, B.; Collaert, N.; Mocuta, A.; Thean, A.; Groeseneken, G.
	Title	Improved source design for p-type tunnel field-effect transistors : towards truly complementary logic			Type	A1 Journal article
	Year	2014	Publication	Applied physics letters	Abbreviated Journal	Appl Phys Lett
	Volume	105	Issue	24	Pages	243506
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Complementary logic based on tunnel field-effect transistors (TFETs) would drastically reduce power consumption thanks to the TFET's potential to obtain a sub-60 mV/dec subthreshold swing (SS). However, p-type TFETs typically do not meet the performance of n-TFETs for direct bandgap III-V configurations. The p-TFET SS stays well above 60 mV/dec, due to the low density of states in the conduction band. We therefore propose a source configuration in which a highly doped region is maintained only near the tunnel junction. In the remaining part of the source, the hot carriers in the exponential tail of the Fermi-Dirac distribution are blocked by reducing the doping degeneracy, either with a source section with a lower doping concentration or with a heterostructure. We apply this concept to n-p-i-p configurations consisting of In0.53Ga0.47As and an InP-InAs heterostructure. 15-band quantum mechanical simulations predict that the configurations with our source design can obtain sub-60 mV/dec SS, with an on-current comparable to the conventional source design. (C) 2014 AIP Publishing LLC.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000346643600076	Publication Date	2014-12-17
	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	3.411	Times cited	10	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: 3.411; 2014 IF: 3.302
	Call Number	UA @ lucian @ c:irua:122798			Serial	1568
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	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	O'Regan, T.P.; Hurley, P.K.; Sorée, B.; Fischetti, M.V.
	Title	Modeling the capacitance-voltage response of In_0.53Ga_0.47As metal-oxide-semiconductor structures : charge quantization and nonparabolic corrections			Type	A1 Journal article
	Year	2010	Publication	Applied Physics Letters	Abbreviated Journal	Appl Phys Lett
	Volume	96	Issue	21	Pages	213514,1-213514,3
	Keywords	A1 Journal article; Electron Microscopy for Materials Science (EMAT);
	Abstract	The capacitance-voltage (C-V) characteristic is calculated for p-type In<sub>0.53</sub>Ga<sub>0.47</sub>As metal-oxide-semiconductor (MOS) structures based on a self-consistent PoissonSchrödinger solution. For strong inversion, charge quantization leads to occupation of the satellite valleys which appears as a sharp increase in the capacitance toward the oxide capacitance. The results indicate that the charge quantization, even in the absence of interface defects (D<sub>it</sub>), is a contributing factor to the experimental observation of an almost symmetric C-V response for In<sub>0.53</sub>Ga<sub>0.47</sub>As MOS structures. In addition, nonparabolic corrections are shown to enhance the depopulation of the Γ valley, shifting the capacitance increase to lower inversion charge densities.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000278183200090	Publication Date	2010-05-28
	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	26	Open Access
	Notes				Approved	Most recent IF: 3.411; 2010 IF: 3.841
	Call Number	UA @ lucian @ c:irua:89509			Serial	2143
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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
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	Author	Andrikopoulos, D.; Sorée, B.; De Boeck, J.
	Title	Skyrmion-induced bound states on the surface of three-dimensional topological insulators			Type	A1 Journal article
	Year	2016	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	119	Issue	119	Pages	193903
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The interaction between the surface of a 3D topological insulator and a skyrmion/anti-skyrmion structure is studied in order to investigate the possibility of electron confinement due to the skyrmion presence. Both hedgehog (Neel) and vortex (Bloch) skyrmions are considered. For the hedgehog skyrmion, the in-plane components cannot be disregarded and their interaction with the surface state of the topological insulator (TI) has to be taken into account. A semi-classical description of the skyrmion chiral angle is obtained using the variational principle. It is shown that both the hedgehog and the vortex skyrmion can induce bound states on the surface of the TI. However, the number and the properties of these states depend strongly on the skyrmion type and the skyrmion topological number N-Sk. The probability densities of the bound electrons are also derived where it is shown that they are localized within the skyrmion region. Published by AIP Publishing.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000377718100013	Publication Date	2016-05-18
	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	8	Open Access
	Notes	; ;			Approved	Most recent IF: 2.068
	Call Number	UA @ lucian @ c:irua:134607			Serial	4244
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	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
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	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
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	Author	Duflou, R.; Ciubotaru, F.; Vaysset, A.; Heyns, M.; Sorée, B.; Radu, I.P.; Adelmann, C.
	Title	Micromagnetic simulations of magnetoelastic spin wave excitation in scaled magnetic waveguides			Type	A1 Journal article
	Year	2017	Publication	Applied physics letters	Abbreviated Journal
	Volume	111	Issue	19	Pages	192411
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We study the excitation of spin waves in scaled magnetic waveguides using the magnetoelastic effect. In uniformly magnetized systems, normal strains parallel or perpendicular to the magnetization direction do not lead to spin wave excitation since the magnetoelastic torque is zero. Using micromagnetic simulations, we show that the nonuniformity of the magnetization in submicron waveguides due to the effect of the demagnetizing field leads to the excitation of spin waves for oscillating normal strains both parallel and perpendicular to the magnetization. The excitation by biaxial normal in-plane strain was found to be much more efficient than that by uniaxial normal out-of-plane strain. For narrow waveguides with a width of 200 nm, the excitation efficiency of biaxial normal in-plane strain was comparable to that of shear strain. Published by AIP Publishing.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000414975500027	Publication Date	2017-11-10
	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		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:152599			Serial	8247
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	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	Smets, Q.; Verreck, D.; Verhulst, A.S.; Rooyackers, R.; Merckling, C.; Van De Put, M.; Simoen, E.; Vandervorst, W.; Collaert, N.; Thean, V.Y.; Sorée, B.; Groeseneken, G.; Heyns, M.M.;
	Title	InGaAs tunnel diodes for the calibration of semi-classical and quantum mechanical band-to-band tunneling models			Type	A1 Journal article
	Year	2014	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	115	Issue	18	Pages	184503-184509
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Promising predictions are made for III-V tunnel-field-effect transistor (FET), but there is still uncertainty on the parameters used in the band-to-band tunneling models. Therefore, two simulators are calibrated in this paper; the first one uses a semi-classical tunneling model based on Kane's formalism, and the second one is a quantum mechanical simulator implemented with an envelope function formalism. The calibration is done for In0.53Ga0.47As using several p+/intrinsic/n+ diodes with different intrinsic region thicknesses. The dopant profile is determined by SIMS and capacitance-voltage measurements. Error bars are used based on statistical and systematic uncertainties in the measurement techniques. The obtained parameters are in close agreement with theoretically predicted values and validate the semi-classical and quantum mechanical models. Finally, the models are applied to predict the input characteristics of In0.53Ga0.47As n- and p-lineTFET, with the n-lineTFET showing competitive performance compared to MOSFET.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000336919400048	Publication Date	2014-05-14
	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	34	Open Access
	Notes	; Quentin Smets and Devin Verreck gratefully acknowledge the support of a Ph. D. stipend from IWT-Vlaanderen. This work was supported by imec's industrial affiliation program. The authors thank Kim Baumans, Johan Feyaerts, Johan De Cooman, Alireza Alian, and Jos Moonens for their support in process development; Bastien Douhard and Joris Delmotte for SIMS characterization; Alain Moussa for AFM characterization; Joris Van Laer and Tom Daenen for their support in electrical characterization; Kuo-Hsing Kao, Mehbuba Tanzid, and Ali Pourghaderi for their support in modeling. ;			Approved	Most recent IF: 2.068; 2014 IF: 2.183
	Call Number	UA @ lucian @ c:irua:118009			Serial	1667
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	Author	Devolder, T.; Bultynck, O.; Bouquin, P.; Nguyen, V.D.; Rao, S.; Wan, D.; Sorée, B.; Radu, I.P.; Kar, G.S.; Couet, S.
	Title	Back hopping in spin transfer torque switching of perpendicularly magnetized tunnel junctions			Type	A1 Journal article
	Year	2020	Publication	Physical Review B	Abbreviated Journal	Phys Rev B
	Volume	102	Issue	18	Pages	184406
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We analyze the phenomenon of back hopping in spin-torque induced switching of the magnetization in perpendicularly magnetized tunnel junctions. The analysis is based on single-shot time-resolved conductance measurements of the pulse-induced back hopping. Studying several material variants reveals that the back hopping is a feature of the nominally fixed system of the tunnel junction. The back hopping is found to proceed by two sequential switching events that lead to a final state P' of conductance close to-but distinct from-that of the conventional parallel state. The P' state does not exist at remanence. It generally relaxes to the conventional antiparallel state if the current is removed. The P' state involves a switching of the sole spin-polarizing part of the fixed layers. The analysis of literature indicates that back hopping occurs only when the spin-polarizing layer is too weakly coupled to the rest of the fixed system, which justifies a posteriori the mitigation strategies of back hopping that were implemented empirically in spin-transfer-torque magnetic random access memories.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000587594900005	Publication Date	2020-11-09
	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	3.7	Times cited		Open Access
	Notes	; This work was supported in part by the IMEC's Industrial Affiliation Program on STT-MRAM device, and in part by the imec IIAP core CMOS and the Beyond CMOS program of Intel Corporation. T. D. and P. B. thank Jonathan Z. Sun for constructive discussions on the BH phenomenon. ;			Approved	Most recent IF: 3.7; 2020 IF: 3.836
	Call Number	UA @ admin @ c:irua:173524			Serial	6458
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	Author	Beckers, A.; Thewissen, M.; Sorée, B.
	Title	Energy filtering in silicon nanowires and nanosheets using a geometric superlattice and its use for steep-slope transistors			Type	A1 Journal article
	Year	2018	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	124	Issue	14	Pages	144304
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	This paper investigates energy filtering in silicon nanowires and nanosheets by resonant electron tunneling through a geometric superlattice. A geometric superlattice is any kind of periodic geometric feature along the transport direction of the nanowire or nanosheet. Multivalley quantum-transport simulations are used to demonstrate the manifestation of minibands and minibandgaps in the transmission spectra of such a superlattice. We find that the presence of different valleys in the conduction band of silicon favors a nanowire with a rectangular cross section for effective energy filtering. The obtained energy filter can consequently be used in the source extension of a field-effect transistor to prevent high-energy electrons from contributing to the leakage current. Self-consistent Schrodinger-Poisson simulations in the ballistic limit show minimum subthreshold swings of 6 mV/decade for geometric superlattices with indentations. The obtained theoretical performance metrics for the simulated devices are compared with conventional III-V superlatticeFETs and TunnelFETs. The adaptation of the quantum transmitting boundary method to the finite-element simulation of 3-D structures with anisotropic effective mass is presented in Appendixes A and B. Our results bare relevance in the search for steep-slope transistor alternatives which are compatible with the silicon industry and can overcome the power-consumption bottleneck inherent to standard CMOS technologies. Published by AIP Publishing.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000447148100011	Publication Date	2018-10-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979; 1089-7550	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	3	Open Access
	Notes	; ;			Approved	Most recent IF: 2.068
	Call Number	UA @ lucian @ c:irua:154729UA @ admin @ c:irua:154729			Serial	5099
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	Author	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	Osca, J.; Sorée, B.
	Title	Torque field and skyrmion motion by spin transfer torque in a quasi-2D interface in presence of strong spin-orbit interaction			Type	A1 Journal article
	Year	2021	Publication	Journal Of Applied Physics	Abbreviated Journal	J Appl Phys
	Volume	130	Issue	13	Pages	133903
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We investigate the torque field and skyrmion motion at an interface between a ferromagnet hosting a skyrmion and a material with a strong spin-orbit interaction. We analyze both semiconductor materials and topological insulators using a Hamiltonian model that includes a linear term. The spin torque-inducing current is considered to flow in the single band limit; therefore, a quantum model of current is used. Skyrmion motion due to spin transfer torque proves to be more difficult in the presence of a spin-orbit interaction in the case where only interface in-plane currents are present. However, edge effects in narrow nanowires can be used to drive the skyrmion motion and to exert a limited control on its motion direction. We also show the differences and similarities between torque fields due to electric current in the many and single band limits. Published under an exclusive license by AIP Publishing.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000755090400003	Publication Date	2021-10-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979; 1089-7550	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 2.068
	Call Number	UA @ admin @ c:irua:186452			Serial	7034
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	Author	Osca, J.; Sorée, B.
	Title	Skyrmion spin transfer torque due to current confined in a nanowire			Type	A1 Journal article
	Year	2020	Publication	Physical Review B	Abbreviated Journal	Phys Rev B
	Volume	102	Issue	12	Pages	125436
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	In this work we compute the torque field present in a ferromagnet in contact with a metallic nanowire when a skyrmion is present. If the nanowire is narrow enough, then the current is carried by a single conduction band. In this regime the classical torque model breaks down and we show that a skyrmion driven by spin transfer torque moves in a different direction than predicted by the classical model. However, the amount of charge current required to move a skyrmion with a certain velocity in the single-band regime is similar to a classical model of torque where it is implicitly assumed current transport by many conduction bands. The single-band regime is more efficient creating spin current from charge current because of the perfect polarization of the single band but is less efficient creating torque from spin current. Nevertheless, it is possible to take profit of the single-band regime to move skyrmions even with no net charge or spin current flowing between the device contacts. We have also been able to recover the classical limit considering an ensemble of only a few electronic states. In this limit we have discovered that electron diffusion needs to be considered even in ballistic nanowires due the effect of the skyrmion structure on the electron current.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000573775300004	Publication Date	2020-09-30
	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	3.7	Times cited		Open Access
	Notes	; The authors thanks Llorenc Serra for useful discussion on the conduction electron quantum model. We also want to show gratitude to Dimitrios Andrikopoulos for sharing his knowledge about the available bibliography and to F. J. P. van Duijn for his comments on earlier versions of this manuscript. We acknowledge the Horizon 2020 project SKYTOP “Skyrmion-Topological Insulator and Weyl Semimetal Technology” (FETPROACT-2018-01, No. 824123). Finally, J.O. also acknowledges the postdoctoral fellowship provided by KU Leuven. ;			Approved	Most recent IF: 3.7; 2020 IF: 3.836
	Call Number	UA @ admin @ c:irua:172727			Serial	6604
Permanent link to this record



	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
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	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
Permanent link to this record



	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	Deylgat, E.; Chen, E.; Fischetti, M.V.; Sorée, B.; Vandenberghe, W.G.
	Title	Image-force barrier lowering in top- and side-contacted two-dimensional materials			Type	A1 Journal article
	Year	2022	Publication	Solid state electronics	Abbreviated Journal	Solid State Electron
	Volume	198	Issue		Pages	108458-4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We compare the image-force barrier lowering (IFBL) and calculate the resulting contact resistance for four different metal-dielectric-two-dimensional (2D) material configurations. We analyze edge contacts in three different geometries (a homogeneous dielectric throughout, including the 2D layer; a homogeneous dielectric surrounding the 2D layer, both ungated and back gated) and also a top-contact assuming a homogeneous dielectric. The image potential energy of each configuration is determined and added to the Schottky energy barrier which is calculated assuming a textbook Schottky potential. For each configuration, the contact resistivity is calculated using the WKB approximation and the effective mass approximation using either SiO2 or HfO2 as the surrounding dielectric. We obtain the lowest contact resistance of 1 k Omega mu m by n-type doping an edge contacted transition metal-dichalcogenide (TMD) monolayer, sandwiched between SiO2 dielectric, with similar to 1012 cm-2 donor atoms. When this optimal configuration is used, the contact resistance is lowered by a factor of 50 compared to the situation when the IFBL is not considered.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000876289800003	Publication Date	2022-09-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0038-1101	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor	1.7	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 1.7
	Call Number	UA @ admin @ c:irua:191556			Serial	7312
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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.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	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	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	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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