58 citations · 121 across the 20 of their papers we have counts for
21 papers
General boundary conditions for the quasiclassical kinetic equations in the presence of magnetism and unconventional superconductivity
Tim Kokkeler, Yukio Tanaka, F. Sebastian Bergeret
We present boundary conditions for the quasiclassical Green's functions describing spin active interfaces between two materials, at least one of which is in the diffusive regime. T…
Theory of Spin-splitter Magnetoresistance in Altermagnets
Tim Kokkeler, Vitaly N. Golovach, F. Sebastian Bergeret
We develop a theory of angular-dependent magnetoresistance (ADMR) in metallic altermagnets coupled to ferromagnetic insulators and establish criteria that distinguish them from con…
Controlling magnetic domain walls with supercurrents
Tim Kokkeler, Risto Ojajärvi, F. Sebastian Bergeret +1
Establishing a versatile, fast and reliable magnetic memory technology is a giant bottleneck for cryogenic computing since present-day room-temperature solutions either cease to wo…
Spin Splitter and Inverse Effects in Altermagnetic Hybrid Structures
Nicolás Sigales, Tim Kokkeler, Gonzalo de Polsi +1
We provide a theoretical description of diffusive charge and spin transport in hybrid devices containing altermagnets. Based on recently derived drift--diffusion equations for coup…
Direct demonstration of time-reversal-symmetry-breaking spin injection from a compensated magnet
Jone Mencos, Antonin Badura, Eoin Dolan +21
The injection, propagation and detection of spin currents are essential physical processes in spintronics. So far, the separation of charge and spin currents was facilitated by the…
Interplay between Superconductivity and Altermagnetism in Disordered Materials and Heterostructures
Rodrigo de las Heras, Tim Kokkeler, Stefan Ilić +2
We study the interplay between superconductivity and altermagnetism in disordered systems using recently derived quantum kinetic transport equations. Starting from this framework,…
Nonequilibrium spin-splitter effect in altermagnet superconductor hybrids
Tim Kokkeler, Tero T. Heikkilä, F. Sebastian Bergeret
We study the nonequilibrium spin-splitter effect in superconducting altermagnets and superconductor altermagnet hybrids by computing the alternating spin current and edge the spin…
Fluxoid solitons in superconducting tapered tubes and bottlenecks
Tim Kokkeler, Mateo Uldemolins, Francisco Lobo +3
A thin-walled tubular superconductor develops a quantized fluxoid in the presence of an axial magnetic field. The fluxoid corresponds to the number of phase windings of the superco…
From local to collective superconductivity in proximitized graphene
Stefano Trivini, Tim Kokkeler, Jon Ortuzar +8
The superconducting proximity effect induces pairing correlations in metallic systems via Andreev scattering. This effect is particularly intriguing in graphene, as it enables two-…
Interfacial spin-orbit coupling in superconducting hybrid systems
A. A. Mazanik, Tim Kokkeler, I. V. Tokatly +1
We investigate the effects of interfacial spin-orbit coupling (ISOC) on superconductors, focusing on its impact on electronic transport and spin-charge conversion. Using a symmetry…
Quantum transport theory for unconventional magnets: Interplay of altermagnetism and p-wave magnetism with superconductivity
Tim Kokkeler, Ilya Tokatly, F. Sebastian Bergeret
We present a quantum transport theory for generic magnetic metals, in which magnetism occurs predominantly due to exchange interactions, such as ferromagnets, antiferromagnets, alt…
Full counting statistics for unconventional superconductor junctions
Tim Kokkeler, Alexander Golubov, F. Sebastian Bergeret +1
Noise and current measurements are key tools for studying mesoscopic systems, revealing insights beyond conductance alone. For instance, noise measurements show that transport carr…
A universal phenomenology of charge-spin interconversion and dynamics in diffusive systems with spin-orbit coupling
Tim Kokkeler, F. Sebastian Bergeret, Ilya Tokatly
We present an effective field theory for a unified description of transport in normal and superconducting metals in the presence of generic spin-orbit coupling (SOC). The structure…
Positive magnetoresistance in anapole superconductor junctions
Tim Kokkeler, Yukio Tanaka, Alexander Golubov
The article presents a method to detect time-reversal symmetry breaking in non-centrosymmetric superconductors using only transport measurements. Specifically, if time-reversal sym…
Nonreciprocal superconducting transport and the spin Hall effect in gyrotropic structures
Tim Kokkeler, Ilya Tokatly, Sebastian Bergeret
The search for superconducting systems exhibiting nonreciprocal transport and, specifically, the diode effect, has proliferated in recent years. This trend encompasses a wide varie…
Proximity effect of time-reversal symmetry broken non-centrosymmetric superconductors
Tim Kokkeler, Alexander Golubov, Sebastián Bergeret +1
In non-centrosymmetric superconductors the pair potential has both even-parity singlet and odd-parity triplet components. If time-reversal symmetry is broken, the superconducting p…
Spectroscopic signature of spin triplet odd-valley superconductivity in two-dimensional materials
T. H. Kokkeler, Chunli Huang, F. S. Bergeret +1
Motivated by recent discoveries of superconductivity in lightly-doped multilayer graphene systems, we present a low-energy model to study superconductivity in 2D materials whose Fe…
Anisotropic differential conductance of a mixed parity superconductor/ferromagnet structure
Tim Kokkeler, Alberto Hijano, F. Sebastián Bergeret
We study the electronic transport properties of a superconductor (S) with a mixed s+p-wave pairing attached to a ferromagnetic metal (F) and a normal electrode (N) in an SFN config…
Field-free anomalous junction and superconducting diode effect in spin split superconductor/topological insulator junctions
Tim Kokkeler, F. Sebastián Bergeret, Alexander Golubov
We study the transport properties of a diffusive Josephson junction between two spin-split superconductors made of superconductor-ferromagnetic insulator bilayers (FIS) on top of a…
Spin conductance in SNN junctions with non-centrosymmetric superconductors
Tim Kokkeler, Yukio Tanaka, Alexander A. Golubov
An SNN-junction in which the superconducting potential is a mixture between s-wave and p-wave potentials is investigated using the Usadel equation equipped with Tanaka-Nazarov boun…
Theory of proximity effect in -wave superconductor junctions
Yukio Tanaka, Tim Kokkeler, Alexander Golubov
We derive a boundary condition for the Nambu Keldysh Green's function in diffusive normal metal / unconventional superconductor junctions applicable for mixed parity pairing. Apply…