388 citations · 1.8k across the 41 of their papers we have counts for
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SuperConga: an open-source framework for mesoscopic superconductivity
P. Holmvall, N. Wall Wennerdal, M. Håkansson +4
We present SuperConga, an open-source framework for simulating equilibrium properties of unconventional and ballistic singlet superconductors, confined to two-dimensional (2D) meso…
A finite element method for the quasiclassical theory of superconductivity
Kevin Marc Seja, Tomas Lofwander
The Eilenberger-Larkin-Ovchinnikov-Eliashberg quasiclassical theory of superconductivity is a powerful method enabling studies of a wide range of equilibrium and non-equilibrium ph…
Self-consistent theory of current injection into and superconductors
Kevin Marc Seja, Tomas Löfwander
We present results for the steady-state nonlinear response of a superconducting film connected to normal-metal reservoirs under voltage bias, allowing for a subdomina…
Quasiclassical theory of charge transport across mesoscopic normal metal-superconducting heterostructures with current conservation
Kevin Marc Seja, Tomas Löfwander
We consider the steady-state nonequilibrium behavior of mesoscopic superconducting wires connected to normal-metal reservoirs. Going beyond the diffusive limit, we utilize the quas…
Disorder-robust phase crystal in high-temperature superconductors stabilized by strong correlations
Debmalya Chakraborty, Tomas Löfwander, Mikael Fogelström +1
The simultaneous interplay of strong electron-electron correlations, topological zero-energy states, and disorder is yet an unexplored territory but of immense interest due to thei…
Breaking time-reversal and translational symmetry at edges of -wave superconductors: microscopic theory and comparison with quasiclassical theory
N. Wall Wennerdal, A. Ask, P. Holmvall +2
We report results of a microscopic calculation of a second-order phase transition into a state breaking time-reversal and translational invariance along pair-breaking edges of -…
Phase Crystals
P. Holmvall, M. Fogelström, T. Löfwander +1
Superconductivity owes its properties to the phase of the electron pair condensate that breaks the symmetry. In the most traditional ground state, the phase is uniform and r…
Spontaneous symmetry-breaking at surfaces of -wave superconductors: influence of geometry and surface ruggedness
P. Holmvall, A. Vorontsov, M. Fogelstrom +1
Surfaces of -wave superconductors may host a substantial density of zero-energy Andreev states. The zero-energy flat band appears due to a topological constraint, but comes with…
Spontaneously broken translational symmetry at edges of high-temperature superconductors: thermodynamics in magnetic field
P. Holmvall, A. B. Vorontsov, M. Fogelstrom +1
We investigate equilibrium properties, including structure of the order parameter, superflow patterns, and thermodynamics of low-temperature surface phases of layered d_{x^2-y^2}-w…
Spontaneous generation of fractional vortex-antivortex pairs at single edges of high-Tc superconductors
Patric Holmvall, Tomas Löfwander, Mikael Fogelström
Unconventional d-wave superconductors with pair-breaking edges are predicted to have ground states with spontaneously broken time-reversal and translational symmetries. We use the…
Spontaneously broken time-reversal symmetry in high-temperature superconductors
Mikael Håkansson, Tomas Löfwander, Mikael Fogelström
Conventional superconductors are strong diamagnets that through the Meissner effect expel magnetic fields. It would therefore be surprising if a superconducting ground state would…
Andreev spectroscopy of CrO thin films on TiO and AlO
KA Yates, MS Anwar, J Aarts +4
Here we analyse the spectroscopic information gathered at a number of single CrO / Pb interfaces. We examine thin films requiring additional interfacial layers to generate lo…
Inverse proximity effect and influence of disorder on triplet supercurrents in strongly spin-polarized ferromagnets
Roland Grein, Tomas Lofwander, Matthias Eschrig
We discuss the Josephson effect in strongly spin-polarized ferromagnets where triplet correlations are induced by means of spin-active interface scattering, extending our earlier w…
Is CrO Fully Spin-Polarized? - Analysis of Andreev Spectra and Excess Current
Tomas Lofwander, Roland Grein, Matthias Eschrig
We report an extensive theoretical analysis of point-contact Andreev reflection data available in literature on ferromagnetic CrO. We find that the spectra can be well understo…
Theory of superconductor-ferromagnet point contact spectra: the case of strong spin polarization
Roland Grein, Tomas Lofwander, Georgo Metalidis +1
We study the impact of spin-active scattering on Andreev spectra of point contacts between superconductors(SCs) and strongly spin-polarized ferromagnets(FMs) using recently derived…
Spectrum of Andreev Bound States in a Molecule Embedded Inside a Microwave-Excited Superconducting Junction
Jonas Skoldberg, Tomas Lofwander, Vitaly S. Shumeiko +1
Non-dissipative Josephson current through nanoscale superconducting constrictions is carried by spectroscopically sharp energy states, so-called Andreev bound states. Although theo…
0-pi Transitions in a Superconductor/Chiral Ferromagnet/Superconductor Junction induced by a Homogeneous Cycloidal Spiral
Thierry Champel, Tomas Löfwander, Matthias Eschrig
We study the pi phase in a superconductor-ferromagnet-superconductor Josephson junction, with a ferromagnet showing a cycloidal spiral spin modulation with in-plane propagation vec…
Triplet supercurrents in clean and disordered half-metallic ferromagnets
M. Eschrig, T. Löfwander
Interfaces between materials with differently ordered phases present unique opportunities to study fundamental problems in physics. One example is the interface between a singlet s…
Symmetries of Pairing Correlations in Superconductor-Ferromagnet Nanostructures
M. Eschrig, T. Lofwander, T. Champel +3
Using selection rules imposed by the Pauli principle, we classify pairing correlations according to their symmetry properties with respect to spin, momentum, and energy. We observe…
Observation of Periodic pi-Phase Shifts in Ferromagnet-Superconductor Multilayers
V. Shelukhin, A. Tsukernik, M. Karpovski +8
We report complementary studies of the critical temperature and the critical current in ferromagnet (Ni) - superconductor (Nb) multilayers. The observed oscillatory behavior of bot…
Interplay of Magnetic and Superconducting Proximity Effects in FSF Trilayers
Tomas Lofwander, Thierry Champel, Johannes Durst +1
We present theoretical results on the interplay of magnetic and superconducting orders in diffusive ferromagnet-superconductor-ferromagnet trilayers. The induced triplet supercondu…
Low-Temperature Thermal Conductivity of Superconductors With Gap Nodes
Tomas Lofwander, Mikael Fogelstrom
We report a detailed analytic and numerical study of electronic thermal conductivity in d-wave superconductors. We compare theory of the cross over at low temperatures from T-depen…
Nonequilibrium Superconductivity near Spin Active Interfaces
Erhai Zhao, Tomas Lofwander, J. A. Sauls
The Riccati formulation of the quasiclassical theory of nonequilibrium superconductors is developed for spin-dependent scattering near magnetic interfaces. We derive boundary condi…
Shot noise in normal metal-d-wave superconducting junctions
Tomas Lofwander, Mikael Fogelstrom, J. A. Sauls
We present theoretical calculations and predictions for the shot noise in voltage biased junctions of superconductors and normal metal counter-electrodes. In the clea…