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	Author	Mulkers, J.; Milošević, M.V.; Van Waeyenberge, B.
	Title	Cycloidal versus skyrmionic states in mesoscopic chiral magnets			Type	A1 Journal article
	Year	2016	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	93	Issue	93	Pages	214405
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	When subjected to the interfacially induced Dzyaloshinskii-Moriya interaction, the ground state in thin ferromagnetic films with high perpendicular anisotropy is cycloidal. The period of this cycloidal state depends on the strength of the Dzyaloshinskii-Moriya interaction. In this work, we have studied the effect of confinement on the magnetic ground state and excited states, and we determined the phase diagram of thin strips and thin square platelets by means of micromagnetic calculations. We show that multiple cycloidal states with different periods can be stable in laterally confined films, where the period of the cycloids does not depend solely on the Dzyaloshinskii-Moriya interaction strength but also on the dimensions of the film. The more complex states comprising skyrmions are also found to be stable, though with higher energy.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000377298600006	Publication Date	2016-06-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	28	Open Access
	Notes	; ;			Approved	Most recent IF: 3.836
	Call Number	c:irua:133919			Serial	4081
Permanent link to this record



	Author	Zhang, L.; Fernández Becerra, V.; Covaci, L.; Milošević, M.V.
	Title	Electronic properties of emergent topological defects in chiral p-wave superconductivity			Type	A1 Journal article
	Year	2016	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	94	Issue	94	Pages	024520
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Chiral p-wave superconductors in applied magnetic field can exhibit more complex topological defects than just conventional superconducting vortices, due to the two-component order parameter (OP) and the broken time-reversal symmetry. We investigate the electronic properties of those exotic states, some of which contain clusters of one-component vortices in chiral components of the OP and/or exhibit skyrmionic character in the relative OP space, all obtained as a self-consistent solution of the microscopic Bogoliubov-de Gennes equations. We reveal the link between the local density of states (LDOS) of the novel topological states and the behavior of the chiral domain wall between the OP components, enabling direct identification of those states in scanning tunneling microscopy. For example, a skyrmion always contains a closed chiral domain wall, which is found to be mapped exactly by zero-bias peaks in LDOS. Moreover, the LDOS exhibits electron-hole asymmetry, which is different from the LDOS of conventional vortex states with same vorticity. Finally, we present the magnetic field and temperature dependence of the properties of a skyrmion, indicating that this topological defect can be surprisingly large in size, and can be pinned by an artificially indented nonsuperconducting closed path in the sample. These features are expected to facilitate the experimental observation of skyrmionic states, thereby enabling experimental verification of chirality in emerging superconducting materials.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000381479500002	Publication Date	2016-07-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9969	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	27	Open Access
	Notes	; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO). ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:135742			Serial	4303
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	Author	Bekaert, J.; Vercauteren, S.; Aperis, A.; Komendová, L.; Prozorov, R.; Partoens, B.; Milošević, M.V.
	Title	Anisotropic type-I superconductivity and anomalous superfluid density in OsB2			Type	A1 Journal article
	Year	2016	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	94	Issue	94	Pages	144506
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We present a microscopic study of superconductivity in OsB2 , and discuss the origin and characteristic length scales of the superconducting state. From first-principles we show that OsB2 is characterized by three different Fermi sheets, and we prove that this fermiology complies with recent quantum-oscillation experiments. Using the found microscopic properties, and experimental data from the literature, we employ Ginzburg-Landau relations to reveal that OsB2 is a distinctly type-I superconductor with a very low Ginzburg-Landau parameter κ—a rare property among compound materials. We show that the found coherence length and penetration depth corroborate the measured thermodynamic critical field. Moreover, our calculation of the superconducting gap structure using anisotropic Eliashberg theory and ab initio calculated electron-phonon interaction as input reveals a single but anisotropic gap. The calculated gap spectrum is shown to give an excellent account for the unconventional behavior of the superfluid density of OsB2 measured in experiments as a function of temperature. This reveals that gap anisotropy can explain such behavior, observed in several compounds, which was previously attributed solely to a two-gap nature of superconductivity.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000385622500009	Publication Date	2016-10-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	19	Open Access
	Notes	Fonds Wetenschappelijk Onderzoek; European Cooperation in Science and Technology, MP1201 ; Vetenskapsrådet;			Approved	Most recent IF: 3.836
	Call Number	CMT @ cmt @ c:irua:139020			Serial	4338
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	Author	Fernández Becerra, V.; Milošević, M.V.
	Title	Multichiral ground states in mesoscopic p-wave superconductors			Type	A1 Journal article
	Year	2016	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	94	Issue	94	Pages	184517
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Using Ginzburg-Landau formalism, we investigate the effect of confinement on the ground state of mesoscopic chiral p-wave superconductors in the absence of magnetic field. We reveal stable multichiral states with domain walls separating the regions with different chiralities, as well as monochiral states with spontaneous currents flowing along the edges. We show that multichiral states can exhibit identifying signatures in the spatial profile of the magnetic field if those are not screened by edge currents in the case of strong confinement. Such magnetic detection of domain walls in topological superconductors can serve as long-sought evidence of broken time-reversal symmetry. Furthermore, when applying electric current to mesoscopic p-wave samples, we found a hysteretic behavior in the current-voltage characteristic that distinguishes states with and without domain walls, thereby providing another useful hallmark for indirect confirmation of chiral p-wave superconductivity.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000388816700001	Publication Date	2016-11-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9950;2469-9969;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	7	Open Access
	Notes	; This work was supported by the Research Foundation-Flanders (FWO-Vlaanderen), the COST-EU action MP1201, and the MultiSuper network. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:139241			Serial	4456
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	Author	Mulkers, J.; Van Waeyenberge, B.; Milošević, M.V.
	Title	Effects of spatially engineered Dzyaloshinskii-Moriya interaction in ferromagnetic films			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	95	Pages	144401
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The Dzyaloshinskii-Moriya interaction (DMI) is a chiral interaction that favors formation of domain walls. Recent experiments and ab initio calculations show that there are multiple ways to modify the strength of the interfacially induced DMI in thin ferromagnetic films with perpendicular magnetic anisotropy. In this paper we reveal theoretically the effects of spatially varied DMI on the magnetic state in thin films. In such heterochiral 2D structures we report several emergent phenomena, ranging from the equilibrium spin canting at the interface between regions with different DMI, over particularly strong confinement of domain walls and skyrmions within high-DMI tracks, to advanced applications such as domain tailoring nearly at will, design of magnonic waveguides, and much improved skyrmion racetrack memory.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000399382100003	Publication Date	2017-04-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	60	Open Access
	Notes	Fonds Wetenschappelijk Onderzoek, G098917N ;			Approved	Most recent IF: 3.836
	Call Number	CMT @ cmt @ c:irua:141917			Serial	4534
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	Author	Houben, K.; Couet, S.; Trekels, M.; Menendez, E.; Peissker, T.; Seo, J.W.; Hu, M.Y.; Zhao, J.Y.; Alp, E.E.; Roelants, S.; Partoens, B.; Milošević, M.V.; Peeters, F.M.; Bessas, D.; Brown, S.A.; Vantomme, A.; Temst, K.; Van Bael, M.J.
	Title	Lattice dynamics in Sn nanoislands and cluster-assembled films			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	15	Pages	155413
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	To unravel the effects of phonon confinement, the influence of size and morphology on the atomic vibrations is investigated in Sn nanoislands and cluster-assembled films. Nuclear resonant inelastic x-ray scattering is used to probe the phonon densities of states of the Sn nanostructures which show significant broadening of the features compared to bulk phonon behavior. Supported by ab initio calculations, the broadening is attributed to phonon scattering and can be described within the damped harmonic oscillator model. Contrary to the expectations based on previous research, the appearance of high-energy modes above the cutoff energy is not observed. From the thermodynamic properties extracted from the phonon densities of states, it was found that grain boundary Sn atoms are bound by weaker forces than bulk Sn atoms.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000401762400008	Publication Date	2017-04-11
	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	5	Open Access
	Notes	; This work was supported by the Research Foundation-Flanders (FWO) and the Concerted Research Action (GOA/14/007). The authors acknowledge Hercules stichting (Projects No. AKUL/13/19 and No. AKUL/13/25). K.H. and S.C. thank the FWO for financial support. T.P. acknowledges the IWT for financial support. S.R., M.V.M., and B.P. acknowledge TOPBOF funding of the University of Antwerp Research Fund. J.W.S. acknowledges Hercules Stichting (Project No. AKUL/13/19). The authors want to thank R. Lieten for help with the XRD measurements and T. Picot for fruitful discussions. The authors gratefully acknowledge R. Ruffer and A. I. Chumakov for fruitful discussions and the European Synchrotron Radiation Facility for the measurement of the SnO<INF>2</INF> powder at the Nuclear Resonance beamline (ID-18). This research used resources of the Advanced Photon Source, a US Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:144305			Serial	4667
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	Author	Stosic, D.; Mulkers, J.; Van Waeyenberge, B.; Ludermir, T.B.; Milošević, M.V.
	Title	Paths to collapse for isolated skyrmions in few-monolayer ferromagnetic films			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	21	Pages	214418
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Magnetic skyrmions are topological spin configurations in materials with chiral Dzyaloshinskii-Moriya interaction (DMI), that are potentially useful for storing or processing information. To date, DMI has been found in few bulk materials, but can also be induced in atomically thin magnetic films in contact with surfaces with large spin-orbit interactions. Recent experiments have reported that isolated magnetic skyrmions can be stabilized even near room temperature in few-atom-thick magnetic layers sandwiched between materials that provide asymmetric spin-orbit coupling. Here we present the minimum-energy path analysis of three distinct mechanisms for the skyrmion collapse, based on ab initio input and the performed atomic-spin simulations. We focus on the stability of a skyrmion in three atomic layers of Co, either epitaxial on the Pt(111) surface or within a hybrid multilayer where DMI nontrivially varies per monolayer due to competition between different symmetry breaking from two sides of the Co film. In laterally finite systems, their constrained geometry causes poor thermal stability of the skyrmion toward collapse at the boundary, which we show to be resolved by designing the high-DMI structure within an extended film with lower or no DMI.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000404015500001	Publication Date	2017-06-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	48	Open Access
	Notes	This work was supported by the Research Foundation, Flanders (FWO-Vlaanderen) and Brazilian agency CNPq (Grants No. 442668/2014-7 and No. 140840/2016-8).			Approved	Most recent IF: 3.836
	Call Number	CMT @ cmt @c:irua:144865			Serial	4704
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	Author	Bekaert, J.; Aperis, A.; Partoens, B.; Oppeneer, P.M.; Milošević, M.V.
	Title	Evolution of multigap superconductivity in the atomically thin limit : strain-enhanced three-gap superconductivity in monolayer MgB₂			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	96	Issue	9	Pages	094510
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Starting from first principles, we show the formation and evolution of superconducting gaps in MgB2 at its ultrathin limit. Atomically thin MgB2 is distinctly different from bulk MgB2 in that surface states become comparable in electronic density to the bulklike sigma and pi bands. Combining the ab initio electron-phonon coupling with the anisotropic Eliashberg equations, we showthat monolayer MgB2 develops three distinct superconducting gaps, on completely separate parts of the Fermi surface due to the emergent surface contribution. These gaps hybridize nontrivially with every extra monolayer added to the film owing to the opening of additional coupling channels. Furthermore, we reveal that the three-gap superconductivity in monolayer MgB2 is robust over the entire temperature range that stretches up to a considerably high critical temperature of 20 K. The latter can be boosted to >50K under biaxial tensile strain of similar to 4%, which is an enhancement that is stronger than in any other graphene-related superconductor known to date.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000410166800008	Publication Date	2017-09-11
	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	56	Open Access
	Notes	; This work was supported by TOPBOF-UAntwerp, Research Foundation-Flanders (FWO), the Swedish Research Council (VR), and the Rontgen-Angstrom Cluster. The first-principles calculations have been carried out on the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Centre (VSC), supported financially by the Hercules Foundation and the Flemish Government (EWI Department). Eliashberg theory calculations were supported through the Swedish National Infrastructure for Computing (SNIC). ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:145623			Serial	4741
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	Author	Zhang, L.-F.; Flammia, L.; Covaci, L.; Perali, A.; Milošević, M.V.
	Title	Multifaceted impact of a surface step on superconductivity in atomically thin films			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	96	Issue	10	Pages	104509
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Recent experiments show that an atomic step on the surface of atomically thin metallic films can strongly affect electronic transport. Here we reveal multiple and versatile effects that such a surface step can have on superconductivity in ultrathin films. By solving the Bogoliubov-de Gennes equations self-consistently in this regime, where quantum confinement dominates the emergent physics, we show that the electronic structure is profoundly modified on the two sides of the step, as is the spatial distribution of the superconducting order parameter and its dependence on temperature and electronic gating. Furthermore, the surface step changes nontrivially the transport properties both in the proximity-induced superconducting pair correlations and the Josephson effect, depending on the step height. These results offer a new route to tailor superconducting circuits and design atomically thin heterojunctions made of one same material.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000411076000012	Publication Date	2017-09-18
	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	7	Open Access
	Notes	; This work was supported by the Research Foundation Flanders (FWO-Vlaanderen), the Special Research Funds of the University of Antwerp (TOPBOF project) and the Italian MIUR through the PRIN 2015 program (Contract No. 2015C5SEJJ001). ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:146750			Serial	4790
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	Author	Stosic, D.; Ludermir, T.B.; Milošević, M.V.
	Title	Pinning of magnetic skyrmions in a monolayer Co film on Pt(111) : Theoretical characterization and exemplified utilization			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	96	Issue	21	Pages	214403
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	<script type='text/javascript'>document.write(unpmarked('Magnetic skyrmions are nanoscale windings of the spin structure that can be observed in chiral magnets and hold promise for potential applications in storing or processing information. Pinning due to ever-present material imperfections crucially affects the mobility of skyrmions. Therefore, a proper understanding of how magnetic skyrmions pin to defects is necessary for the development and performance of spintronic devices. Here we present a fundamental analysis on the interactions of single skyrmions with atomic defects of distinctly different origins, in a Co monolayer on Pt, based on minimum-energy paths considerations and atomic-spin simulations. We first report the preferred pinning loci of the skyrmion as a function of its nominal size and the type of defect being considered, to further reveal the manipulation and \u0022breathing\u0022 of skyrmion core in the vicinity of a defect. We also show the behavior of skyrmions in the presence of an extended defect of particular geometry, that can lead to ratcheted skyrmion motion or a facilitated guidance on a defect \u0022trail.\u0022 We close the study with reflections on the expected thermal stability of the skyrmion against collapse on itself for a given nature of the defect, and discuss the applications where control of skyrmions by defects is of particular interest.'));
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000416846900002	Publication Date	2017-12-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9969; 2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	52	Open Access
	Notes	; This work was supported by the Research Foundation, Flanders (FWO-Vlaanderen) and Brazilian agency CNPq (Grants No. 442668/2014-7 and No. 140840/2016-8). ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:147684			Serial	4890
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	Author	Zhang, L.-F.; Covaci, L.; Milošević, M.V.
	Title	Topological phase transitions in small mesoscopic chiral p-wave superconductors			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	96	Issue	22	Pages	224512
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	<script type='text/javascript'>document.write(unpmarked('Spin-triplet chiral p-wave superconductivity is typically described by a two-component order parameter, and as such is prone to unique emergent effects when compared to the standard single-component superconductors. Here we present the equilibrium phase diagram for small mesoscopic chiral p-wave superconducting disks in the presence of magnetic field, obtained by solving the microscopic Bogoliubov-de Gennes equations self-consistently. In the ultrasmall limit, the cylindrically symmetric giant-vortex states form the ground state of the system. However, with increasing sample size, the cylindrical symmetry is broken as the two components of the order parameter segregate into domains, and the number of fragmented domain walls between them characterizes the resulting states. Such domain walls are topological defects unique for the p-wave order, and constitute a dominant phase in the mesoscopic regime. Moreover, we find two possible types of domain walls, identified by their chirality-dependent interaction with the edge states.'));
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000418653500012	Publication Date	2017-12-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9969; 2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	18	Open Access
	Notes	; This work was supported by the Research Foundation Flanders (FWO-Vlaanderen) and the Special Research Funds of the University of Antwerp. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:148504			Serial	4901
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	Author	Bekaert, J.; Aperis, A.; Partoens, B.; Oppeneer, P.M.; Milošević, M.V.
	Title	Advanced first-principles theory of superconductivity including both lattice vibrations and spin fluctuations : the case of FeB₄			Type	A1 Journal article
	Year	2018	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	97	Issue	1	Pages	014503
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	<script type='text/javascript'>document.write(unpmarked('We present an advanced method to study spin fluctuations in superconductors quantitatively and entirely from first principles. This method can be generally applied to materials where electron-phonon coupling and spin fluctuations coexist. We employ it here to examine the recently synthesized superconductor iron tetraboride (FeB4) with experimental T-c similar to 2.4 K [H. Gou et al., Phys. Rev. Lett, 111, 157002 (2013)]. We prove that FeB4 is particularly prone to ferromagnetic spin fluctuations due to the presence of iron, resulting in a large Stoner interaction strength, I = 1.5 eV, as calculated from first principles. The other important factor is its Fermi surface that consists of three separate sheets, among which two are nested ellipsoids. The resulting susceptibility has a ferromagnetic peak around q = 0, from which we calculated the repulsive interaction between Cooper pair electrons using the random phase approximation. Subsequently, we combined the electron-phonon interaction calculated from first principles with the spin fluctuation interaction in fully anisotropic Eliashberg theory calculations. We show that the resulting superconducting gap spectrum is conventional, yet very strongly depleted due to coupling to the spin fluctuations. The critical temperature decreases from T-c = 41 K, if they are not taken into account, to T-c = 1.7 K, in good agreement with the experimental value.'));
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000419229100004	Publication Date	2018-01-04
	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	23	Open Access
	Notes	; This work was supported by TOPBOF-UAntwerp, Research Foundation Flanders (FWO), the Swedish Research Council (VR), and the Rontgen-Angstrom Cluster. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation Flanders (FWO) and the Flemish Government-department EWI. Anisotropic Eliashberg theory calculations were supported through the Swedish National Infrastructure for Computing (SNIC). ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:148447UA @ admin @ c:irua:148447			Serial	4866
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	Author	Mulkers, J.; Van Waeyenberge, B.; Milošević, M.V.
	Title	Tunable Snell's law for spin waves in heterochiral magnetic films			Type	A1 Journal article
	Year	2018	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	97	Issue	10	Pages	104422
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Thin ferromagnetic films with an interfacially induced DMI exhibit nontrivial asymmetric dispersion relations that lead to unique and useful magnonic properties. Here we derive an analytical expression for the magnon propagation angle within the micromagnetic framework and show how the dispersion relation can be approximated with a comprehensible geometrical interpretation in the k space of the propagation of spin waves. We further explore the refraction of spin waves at DMI interfaces in heterochiral magnetic films, after deriving a generalized Snell's law tunable by an in-plane magnetic field, that yields analytical expressions for critical incident angles. The found asymmetric Brewster angles at interfaces of regions with different DMI strengths, adjustable by magnetic field, support the conclusion that heterochiral ferromagnetic structures are an ideal platform for versatile spin-wave guides.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000428238600006	Publication Date	2018-03-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	20	Open Access
	Notes	This work was supported by the Research Foundation- Flanders (FWO-Vlaanderen) through Project No. G098917N.			Approved	Most recent IF: 3.836
	Call Number	CMT @ cmt @c:irua:150118UA @ admin @ c:irua:150118			Serial	4915
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	Author	Flammia, L.; Zhang, L.-F.; Covaci, L.; Perali, A.; Milošević, M.V.
	Title	Superconducting nanoribbon with a constriction : a quantum-confined Josephson junction			Type	A1 Journal article
	Year	2018	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	97	Issue	13	Pages	134514
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Extended defects are known to strongly affect nanoscale superconductors. Here, we report the properties of superconducting nanoribbons with a constriction formed between two adjacent step edges by solving the Bogoliubov-de Gennes equations self-consistently in the regime where quantum confinement is important. Since the quantum resonances of the superconducting gap in the constricted area are different from the rest of the nanoribbon, such constriction forms a quantum-confined S-S'-S Josephson junction, with a broadly tunable performance depending on the length and width of the constriction with respect to the nanoribbon, and possible gating. These findings provide an intriguing approach to further tailor superconducting quantum devices where Josephson effect is of use.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000430161500004	Publication Date	2018-04-17
	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	7	Open Access
	Notes	; This work was supported by the Research Foundation Flanders (FWO-Vlaanderen), the Special Research Funds of the University of Antwerp (TOPBOF), the Italian MIUR through the PRIN 2015 program (Contract No. 2015C5SEJJ001), the MultiSuper network, and the EU-COST NANOCOHYBRI action CA16218. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:150754UA @ admin @ c:irua:150754			Serial	4980
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	Author	Mulkers, J.; Hals, K.M.D.; Leliaert, J.; Milošević, M.V.; Van Waeyenberge, B.; Everschor-Sitte, K.
	Title	Effect of boundary-induced chirality on magnetic textures in thin films			Type	A1 Journal article
	Year	2018	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	98	Issue	6	Pages	064429
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	In the quest for miniaturizing magnetic devices, the effects of boundaries and surfaces become increasingly important. Here we show how the recently predicted boundary-induced Dzyaloshinskii-Moriya interaction (DMI) affects the magnetization of ferromagnetic films with a C-infinity v symmetry and a perpendicular magnetic anisotropy. For an otherwise uniformly magnetized film, we find a surface twist when the magnetization in the bulk is canted by an in-plane external field. This twist at the surfaces caused by the boundary-induced DMI differs from the common canting caused by internal DMI observed at the edges of a chiral magnet. Furthermore, we find that the surface twist due to the boundary-induced DMI strongly affects the width of the domain wall at the surfaces. We also find that the skyrmion radius increases in the depth of the film, with the average size of the skyrmion increasing with boundary-induced DMI. This increase suggests that the boundary-induced DMI contributes to the stability of the skyrmion.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000443394600004	Publication Date	2018-08-31
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9969; 2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	9	Open Access
	Notes	; The authors thank Matthias Sitte and Andre Thiaville for fruitful discussions. This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vlaanderen) through Project No. G098917N and the German Research Foundation (DFG) under the Project No. EV 196/2-1. J.L. is supported by the Ghent University Special Research Fund with a BOF postdoctoral fellowship. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:153706UA @ admin @ c:irua:153706			Serial	5093
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	Author	Lozano, D.P.; Couet, S.; Petermann, C.; Hamoir, G.; Jochum, J.K.; Picot, T.; Menendez, E.; Houben, K.; Joly, V.; Antohe, V.A.; Hu, M.Y.; Leu, B.M.; Alatas, A.; Said, A.H.; Roelants, S.; Partoens, B.; Milošević, M.V.; Peeters, F.M.; Piraux, L.; Van de Vondel, J.; Vantomme, A.; Temst, K.; Van Bael, M.J.
	Title	Experimental observation of electron-phonon coupling enhancement in Sn nanowires caused by phonon confinement effects			Type	A1 Journal article
	Year	2019	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	99	Issue	6	Pages	064512
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Reducing the size of a superconductor below its characteristic length scales can either enhance or suppress its critical temperature (T-c). Depending on the bulk value of the electron-phonon coupling strength, electronic and phonon confinement effects will play different roles in the modification of T-c. Experimentally disentangling each contribution has remained a challenge. We have measured both the phonon density of states and T-c of Sn nanowires with diameters of 18, 35, and 100 nm in order to quantify the effects of phonon confinement on superconductivity. We observe a shift of the phonon frequency towards the low-energy region and an increase in the electron-phonon coupling constant that can account for the measured increase in T-c.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000459322400005	Publication Date	2019-02-21
	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	8	Open Access
	Notes	; We would like to thanks Jeroen Scheerder and Wout Keijers for their help and assistance during the low-temperature measurements. This work was supported by the Research Foundation Flanders (FWO), the Concerted Research Action (GOA/14/ 007), the Federation Wallonie-Bruxelles (ARC 13/18-052, Supracryst) and the Fonds de la Recherche Scientifique -FNRS under Grant No. T.0006.16. The authors acknowledge Hercules Stichting (Project Nos. AKUL/13/19 and AKUL/13/25). D.P.L. thanks the FWO for financial support. This research used resources of the Advanced Photon Source, a US Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ admin @ c:irua:158621			Serial	5212
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	Author	Menezes, R.M.; Mulkers, J.; de Souza Silva, C.C.; Milošević, M.V.
	Title	Deflection of ferromagnetic and antiferromagnetic skyrmions at heterochiral interfaces			Type	A1 Journal article
	Year	2019	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	99	Issue	10	Pages	104409
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Devising magnetic nanostructures with spatially heterogeneous Dzyaloshinskii-Moriya interaction (DMI) is a promising pathway toward advanced confinement and control of magnetic skyrmions in potential devices. Here we discuss theoretically how a skyrmion interacts with a heterochiral interface using micromagnetic simulations and analytic arguments. We show that a heterochiral interface deflects the trajectory of ferromagnetic (FM) skyrmions, and that the extent of such deflection is tuned by the applied spin-polarized current and the difference in DMI across the interface. Further, we show that this deflection is characteristic of the FM skyrmion, and it is completely absent in the antiferromagnetic (AFM) case. In turn, we reveal that the AFM skyrmion achieves much higher velocities than its FM counterpart, yet experiences far stronger confinement in nanoengineered heterochiral tracks, which reinforces AFM skyrmions as a favorable choice for skyrmion-based devices.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000460720600005	Publication Date	2019-03-07
	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	19	Open Access
	Notes	; This work was supported by the Research Foundation-Flanders (FWO-Vlaanderen) and Brazilian Agencies FACEPE under Grant No. APQ-0198-1.05/14, CAPES and CNPq. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ admin @ c:irua:158557			Serial	5203
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	Author	McNaughton, B.; Milošević, M.V.; Perali, A.; Pilati, S.
	Title	Boosting Monte Carlo simulations of spin glasses using autoregressive neural networks			Type	A1 Journal article
	Year	2020	Publication	Physical Review E	Abbreviated Journal	Phys Rev E
	Volume	101	Issue	5	Pages	053312
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The autoregressive neural networks are emerging as a powerful computational tool to solve relevant problems in classical and quantum mechanics. One of their appealing functionalities is that, after they have learned a probability distribution from a dataset, they allow exact and efficient sampling of typical system configurations. Here we employ a neural autoregressive distribution estimator (NADE) to boost Markov chain Monte Carlo (MCMC) simulations of a paradigmatic classical model of spin-glass theory, namely, the two-dimensional Edwards-Anderson Hamiltonian. We show that a NADE can be trained to accurately mimic the Boltzmann distribution using unsupervised learning from system configurations generated using standard MCMC algorithms. The trained NADE is then employed as smart proposal distribution for the Metropolis-Hastings algorithm. This allows us to perform efficient MCMC simulations, which provide unbiased results even if the expectation value corresponding to the probability distribution learned by the NADE is not exact. Notably, we implement a sequential tempering procedure, whereby a NADE trained at a higher temperature is iteratively employed as proposal distribution in a MCMC simulation run at a slightly lower temperature. This allows one to efficiently simulate the spin-glass model even in the low-temperature regime, avoiding the divergent correlation times that plague MCMC simulations driven by local-update algorithms. Furthermore, we show that the NADE-driven simulations quickly sample ground-state configurations, paving the way to their future utilization to tackle binary optimization problems.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000535862000014	Publication Date	2020-05-28
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1539-3755; 1550-2376	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.366	Times cited	15	Open Access
	Notes	; The authors thank I. Murray, G. Carleo, and F. RicciTersenghi for useful discussions. Financial support from the FAR2018 project titled “Supervised machine learning for quantum matter and computational docking” of the University of Camerino and from the Italian MIUR under Project No. PRIN2017 CEnTraL 20172H2SC4 is gratefully acknowledged. S.P. also acknowledges the CINECA award under the ISCRA initiative, for the availability of high performance computing resources and support. M.V.M. gratefully acknowledges the Visiting Professorship program at the University of Camerino that facilitated the collaboration in this work. ;			Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:170244			Serial	6463
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	Author	Yang, W.; Kong, M.; Milošević, M.V.; Zeng, Z.; Peeters, F.M.
	Title	Two-dimensional binary clusters in a hard-wall trap: structural and spectral properties			Type	A1 Journal article
	Year	2007	Publication	Physical review E	Abbreviated Journal	Phys Rev E
	Volume	76	Issue	4	Pages	art.041404:part 1
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000250621900066	Publication Date	2007-10-24
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1539-3755;1550-2376;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.366	Times cited	9	Open Access
	Notes				Approved	Most recent IF: 2.366; 2007 IF: 2.483
	Call Number	UA @ lucian @ c:irua:67325			Serial	3772
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	Author	Duarte-Neto, P.; Stosic, T.; Stosic, B.; Lessa, R.; Milošević, M.V.
	Title	Interplay of model ingredients affecting aggregate shape plasticity in diffusion-limited aggregation			Type	A1 Journal article
	Year	2014	Publication	Physical review : E : statistical, nonlinear, and soft matter physics	Abbreviated Journal	Phys Rev E
	Volume	90	Issue	1	Pages	012312
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We analyze the combined effect of three ingredients of an aggregation model-surface tension, particle flow and particle source-representing typical characteristics of many aggregation growth processes in nature. Through extensive numerical experiments and for different underlying lattice structures we demonstrate that the location of incoming particles and their preferential direction of flow can significantly affect the resulting general shape of the aggregate, while the surface tension controls the surface roughness. Combining all three ingredients increases the aggregate shape plasticity, yielding a wider spectrum of shapes as compared to earlier works that analyzed these ingredients separately. Our results indicate that the considered combination of effects is fundamental for modeling the polymorphic growth of a wide variety of structures in confined geometries and/or in the presence of external fields, such as rocks, crystals, corals, and biominerals.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	Woodbury (NY)	Editor
	Language		Wos	000341245400009	Publication Date	2014-07-31
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1539-3755;1550-2376;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.366	Times cited	3	Open Access
	Notes	; This work was supported by CNPq, Brazil (Projects No. 201506/2011-4, No. 303251 /2010-7, and No. 306719/2012-6). M.V.M. acknowledges support from Flemish Science Foundation (FWO-Vlaanderen) and CAPES PVE action No. BEX1392/11-5. The crystal structure appearing in Fig. 11 was provided courtesy of L. dos Santos, UFPE, Brazil. ;			Approved	Most recent IF: 2.366; 2014 IF: 2.288
	Call Number	UA @ lucian @ c:irua:119267			Serial	1708
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	Author	Milošević, M.V.; Kanda, A.; Hatsumi, S.; Peeters, F.M.; Ootuka, Y.
	Title	Local current injection into mesoscopic superconductors for the manipulation of quantum states			Type	A1 Journal article
	Year	2009	Publication	Physical review letters	Abbreviated Journal	Phys Rev Lett
	Volume	103	Issue	21	Pages	217003-217003,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We perform strategic current injection in a small mesoscopic superconductor and control the (non)equilibrium quantum states in an applied homogeneous magnetic field. In doing so, we realize a current-driven splitting of multiquanta vortices, current-induced transitions between states with different angular momenta, and current-controlled switching between otherwise degenerate quantum states. These fundamental phenomena form the basis for the electronic and logic applications discussed, and are confirmed in both theoretical simulations and multiple-small-tunnel-junction transport measurements.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York, N.Y.	Editor
	Language		Wos	000272054300044	Publication Date	2009-12-04
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-9007;1079-7114;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.462	Times cited	48	Open Access
	Notes				Approved	Most recent IF: 8.462; 2009 IF: 7.328
	Call Number	UA @ lucian @ c:irua:94498			Serial	1826
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	Author	Silhanek, A.V.; Milošević, M.V.; Kramer, R.B.G.; Berdiyorov, G.R.; Vondel van de, J.; Luccas, R.F.; Puig, T.; Peeters, F.M.; Moshchalkov, V.V.
	Title	Formation of stripelike flux patterns obtained by freezing kinematic vortices in a superconducting Pb film			Type	A1 Journal article
	Year	2010	Publication	Physical review letters	Abbreviated Journal	Phys Rev Lett
	Volume	104	Issue	1	Pages
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We demonstrate experimentally and theoretically that the dissipative state of superconducting samples with a periodic array of holes at high current densities consists of flux rivers resulting from a short-range attractive interaction between vortices. This dynamically induced vortex-vortex attraction results from the migration of quasiparticles out of the vortex core (kinematic vortices). We have directly visualized the formation of vortex chains by scanning Hall probe microscopy after freezing the dynamic state by a field cooling procedure at a constant bias current. Similar experiments carried out in a sample without holes show no hint of flux river formation. We shed light on this nonequilibrium phenomena modeled by time-dependent Ginzburg-Landau simulations.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York, N.Y.	Editor
	Language		Wos	000273881900033	Publication Date	2010-01-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-9007;1079-7114;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.462	Times cited	60	Open Access
	Notes	; This work was supported by Methusalem funding by the Flemish government, the Flemish Science Foundation (FWO-VI), the Belgian Science Policy, and the ESF NES network. A. V. S., G. R. B., and J. V. d. V. acknowledge support from FWO-VI R. F. L. acknowledges support from I3P CSIC program and MAT2008-01022. ;			Approved	Most recent IF: 8.462; 2010 IF: 7.622
	Call Number	UA @ lucian @ c:irua:81009			Serial	1265
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	Author	Shanenko, A.A.; Milošević, M.V.; Peeters, F.M.
	Title	Extended Ginzburg-Landau formalism for two-band superconductors			Type	A1 Journal article
	Year	2011	Publication	Physical review letters	Abbreviated Journal	Phys Rev Lett
	Volume	106	Issue	4	Pages	047005-047005,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Recent observation of unusual vortex patterns in MgB2 single crystals raised speculations about possible type-1.5 superconductivity in two-band materials, mixing the properties of both type-I and type-II superconductors. However, the strict application of the standard two-band Ginzburg-Landau (GL) theory results in simply proportional order parameters of the two bandsand does not support the type-1.5 behavior. Here we derive the extended GL formalism (accounting all terms of the next order over the small τ=1-T/Tc parameter) for a two-band clean s-wave superconductor and show that the two condensates generally have different spatial scales, with the difference disappearing only in the limit T→Tc. The extended version of the two-band GL formalism improves the validity of GL theory below Tc and suggests revisiting the earlier calculations based on the standard model.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York, N.Y.	Editor
	Language		Wos	000286734100010	Publication Date	2011-01-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-9007;1079-7114;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.462	Times cited	84	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-INSTANS network. Discussions with M. D. Croitoru are gratefully acknowledged. ;			Approved	Most recent IF: 8.462; 2011 IF: 7.370
	Call Number	UA @ lucian @ c:irua:88038			Serial	1154
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	Author	Xu, B.; Milošević, M.V.; Lin, S.-H.; Peeters, F.M.; Jankó, B.
	Title	Formation of multiple-flux-quantum vortices in mesoscopic superconductors from simulations of calorimetric, magnetic, and transport properties			Type	A1 Journal article
	Year	2011	Publication	Physical review letters	Abbreviated Journal	Phys Rev Lett
	Volume	107	Issue	5	Pages	057002,1-057002,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Because of strong flux confinement in mesoscopic superconductors, a giant vortex may appear in the ground state of the system in an applied magnetic field. This multiquanta vortex can then split into individual vortices (and vice versa) as a function of, e.g., applied current, magnetic field, or temperature. Here we show that such transitions can be identified by calorimetry, as the formation or splitting of a giant vortex results in a clear jump in measured heat capacity versus external drive. We attribute this phenomenon to an abrupt change in the density of states of the quasiparticle excitations in the vortex core(s), and further link it to a sharp change of the magnetic susceptibility at the transitionproving that the formation of a giant vortex can also be detected by magnetometry.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York, N.Y.	Editor
	Language		Wos	000293333100006	Publication Date	2011-07-29
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-9007;1079-7114;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.462	Times cited	26	Open Access
	Notes	; We thank O. Bourgeois, T. Yokoyama, M. Eschrig, and M. Ichioka for discussions. This work was supported by FWO-Vlaanderen, the Belgian Science Policy (IAP), the bilateral project Flanders-USA, NSF NIRT, ECS-0609249, and Institute of Theoretical Sciences, Notre Dame. ;			Approved	Most recent IF: 8.462; 2011 IF: 7.370
	Call Number	UA @ lucian @ c:irua:91237			Serial	1263
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	Author	Berdiyorov, G.R.; Milošević, M.V.; Covaci, L.; Peeters, F.M.
	Title	Rectification by an imprinted phase in a Josephson junction			Type	A1 Journal article
	Year	2011	Publication	Physical review letters	Abbreviated Journal	Phys Rev Lett
	Volume	107	Issue	17	Pages	177008-177008,5
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	A Josephson phase shift can be induced in a Josephson junction by a strategically nearby pinned Abrikosov vortex (AV). For an asymmetric distribution of an imprinted phase along the junction (controlled by the position of the AV) such a simple system is capable of rectification of ac current in a broad and tunable frequency range. The resulting rectified voltage is a consequence of the directed motion of a Josephson antivortex which forms a pair with the AV when at local equilibrium. The proposed realization of the ratchet potential by an imprinted phase is more efficient than the asymmetric geometry of the junction itself, is easily realizable experimentally, and provides rectification even in the absence of an applied magnetic field.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York, N.Y.	Editor
	Language		Wos	000296985000008	Publication Date	2011-10-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-9007;1079-7114;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.462	Times cited	28	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen) and the Belgian Science Policy (IAP). G. R. B. and L. C. acknowledge individual support from FWO-Vlaanderen. ;			Approved	Most recent IF: 8.462; 2011 IF: 7.370
	Call Number	UA @ lucian @ c:irua:93715			Serial	2847
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	Author	Komendová, L.; Chen, Y.; Shanenko, A.A.; Milošević, M.V.; Peeters, F.M.
	Title	Two-band superconductors : hidden criticality deep in the superconducting state			Type	A1 Journal article
	Year	2012	Publication	Physical review letters	Abbreviated Journal	Phys Rev Lett
	Volume	108	Issue	20	Pages	207002-207002,5
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We show that two-band superconductors harbor hidden criticality deep in the superconducting state, stemming from the critical temperature of the weaker band taken as an independent system. For sufficiently small interband coupling gamma the coherence length of the weaker band exhibits a remarkable deviation from the conventional monotonic increase with temperature, namely, a pronounced peak close to the hidden critical point. The magnitude of the peak scales as proportional to gamma(-mu), with the Landau critical exponent mu = 1/3, the same as found for the mean-field critical behavior with respect to the source field in ferromagnets and ferroelectrics. Here reported hidden criticality of multiband superconductors can be experimentally observed by, e.g., imaging of the variations of the vortex core in a broader temperature range. Similar effects are expected for the superconducting multilayers.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York, N.Y.	Editor
	Language		Wos	000304064000017	Publication Date	2012-05-15
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-9007;1079-7114;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.462	Times cited	75	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl). Useful discussions with A. V. Vagov are acknowledged. ;			Approved	Most recent IF: 8.462; 2012 IF: 7.943
	Call Number	UA @ lucian @ c:irua:98945			Serial	3770
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	Author	Berdiyorov, G.R.; Milošević, M.V.; Latimer, M.L.; Xiao, Z.L.; Kwok, W.K.; Peeters, F.M.
	Title	Large magnetoresistance oscillations in mesoscopic superconductors due to current-excited moving vortices			Type	A1 Journal article
	Year	2012	Publication	Physical review letters	Abbreviated Journal	Phys Rev Lett
	Volume	109	Issue	5	Pages	057004
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We show in the case of a superconducting Nb ladder that a mesoscopic superconductor typically exhibits magnetoresistance oscillations whose amplitude and temperature dependence are different from those stemming from the Little-Parks effect. We demonstrate that these large resistance oscillations (as well as the monotonic background on which they are superimposed) are due to current-excited moving vortices, where the applied current in competition with the oscillating Meissner currents imposes or removes the barriers for vortex motion in an increasing magnetic field. Because of the ever present current in transport measurements, this effect should be considered in parallel with the Little-Parks effect in low-critical temperature (T-c) samples, as well as with recently proposed thermal activation of dissipative vortex-antivortex pairs in high-T-c samples.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York, N.Y.	Editor
	Language		Wos	000306994900024	Publication Date	2012-07-31
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-9007;1079-7114;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.462	Times cited	65	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP) (theory) and by the U. S. Department of Energy (DOE) Award No. DE-FG02-06ER46334 (experiment). G. R. B. acknowledges individual grant from FWO-Vl. W. K. K. acknowledges support from DOE BES under Contract No. DE-AC02-06CH11357, which also funds Argonne's Center for Nanoscale Materials (CNM) where the focused-ion-beam milling was performed. ;			Approved	Most recent IF: 8.462; 2012 IF: 7.943
	Call Number	UA @ lucian @ c:irua:100832			Serial	1780
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	Author	Zhang, L.-F.; Covaci, L.; Milošević, M.V.; Berdiyorov, G.R.; Peeters, F.M.
	Title	Unconventional vortex states in nanoscale superconductors due to shape-induced resonances in the inhomogeneous Cooper-pair condensate			Type	A1 Journal article
	Year	2012	Publication	Physical review letters	Abbreviated Journal	Phys Rev Lett
	Volume	109	Issue	10	Pages	107001
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Vortex matter in mesoscopic superconductors is known to be strongly affected by the geometry of the sample. Here we show that in nanoscale superconductors with coherence length comparable to the Fermi wavelength the shape resonances of the order parameter results in an additional contribution to the quantum topological confinement-leading to unconventional vortex configurations. Our Bogoliubov-de Gennes calculations in a square geometry reveal a plethora of asymmetric, giant multivortex, and vortex-antivortex structures, stable over a wide range of parameters and which are very different from those predicted by the Ginzburg-Landau theory. These unconventional states are relevant for high-T-c nanograins, confined Bose-Einstein condensates, and graphene flakes with proximity-induced superconductivity.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York, N.Y.	Editor
	Language		Wos	000308295700014	Publication Date	2012-09-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-9007;1079-7114;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.462	Times cited	31	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen). ;			Approved	Most recent IF: 8.462; 2012 IF: 7.943
	Call Number	UA @ lucian @ c:irua:101850			Serial	3801
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	Author	Müller, A.; Milošević, M.V.; Dale, S.E.C.; Engbarth, M.A.; Bending, S.J.
	Title	Magnetization measurements and Ginzburg-Landau simulations of micron-size \beta-tin samples : evidence for an unusual critical behavior of mesoscopic type-I superconductors			Type	A1 Journal article
	Year	2012	Publication	Physical review letters	Abbreviated Journal	Phys Rev Lett
	Volume	109	Issue	19	Pages	197003
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We describe investigations of the largely unexplored field of mesoscopic type-I superconductors. Micromagnetometry and 3D Ginzburg-Landau simulations of our single crystal β-tin samples in this regime reveal size- and temperature-dependent supercritical fields whose behavior is radically different from the bulk critical field HcB. We find that complete suppression of the intermediate state in medium-size samples can result in a surprising reduction of the critical field significantly below HcB. We also reveal an evolution of the superconducting-to-normal phase transition from the expected irreversible first order at low temperatures through the previously unobserved reversible first-order to a second-order transition close to Tc, where the critical field can be many times larger than HcB. Finally, we have identified striking correlations between the mesoscopic Hc3 for nucleation of surface superconductivity and the thermodynamic Hc near Tc. All these observations are entirely unexpected in the conventional type-I picture.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York, N.Y.	Editor
	Language		Wos	000310853100017	Publication Date	2012-11-09
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-9007;1079-7114;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.462	Times cited	21	Open Access
	Notes	; This work was supported by the EPSRC-UK under Grant No. EP/E039944/1, and the Flemish Science Foundation (FWO). ;			Approved	Most recent IF: 8.462; 2012 IF: 7.943
	Call Number	UA @ lucian @ c:irua:102401			Serial	1893
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	Author	Bekaert, J.; Petrov, M.; Aperis, A.; Oppeneer, P.M.; Milošević, M.V.
	Title	Hydrogen-induced high-temperature superconductivity in two-dimensional materials : the example of hydrogenated monolayer MgB₂			Type	A1 Journal article
	Year	2019	Publication	Physical review letters	Abbreviated Journal	Phys Rev Lett
	Volume	123	Issue	7	Pages	077001
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Hydrogen-based compounds under ultrahigh pressure, such as the polyhydrides H3S and LaH10, superconduct through the conventional electron-phonon coupling mechanism to attain the record critical temperatures known to date. Here we exploit the intrinsic advantages of hydrogen to strongly enhance phonon-mediated superconductivity in a completely different system, namely, a two-dimensional material with hydrogen adatoms. We find that van Hove singularities in the electronic structure, originating from atomiclike hydrogen states, lead to a strong increase of the electronic density of states at the Fermi level, and thus of the electron-phonon coupling. Additionally, the emergence of high-frequency hydrogen-related phonon modes in this system boosts the electron-phonon coupling further. As a concrete example, we demonstrate the effect of hydrogen adatoms on the superconducting properties of monolayer MgB2, by solving the fully anisotropic Eliashberg equations, in conjunction with a first-principles description of the electronic and vibrational states, and their coupling. We show that hydrogenation leads to a high critical temperature of 67 K, which can be boosted to over 100 K by biaxial tensile strain.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000480611900017	Publication Date	2019-08-14
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-9007	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.462	Times cited	42	Open Access
	Notes	; This work was supported by TOPBOF-UAntwerp, Research Foundation-Flanders (FWO), the Swedish Research Council (VR), the Rontgen-Angstrom Cluster, and the EU-COST Action CA16218. J.B. acknowledges support of a postdoctoral fellowship of the FWO. The computational resources and services used for the first principles calculations in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government-department EWI. Eliashberg theory calculations were supported through the Swedish National Infrastructure for Computing (SNIC). We would also like to acknowledge useful discussions with Bart Partoens, Jacques Tempere, and Matthieu Verstraete. ;			Approved	Most recent IF: 8.462
	Call Number	UA @ admin @ c:irua:161816			Serial	5415
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