206 citations · 3.2k across the 95 of their papers we have counts for
34 papers · 1 filter
Irreducible momentum-space spin structure of Weyl semimetals and its signatures in Friedel oscillations
Andy Knoll, Carsten Timm
Materials that break time-reversal or inversion symmetry possess nondegenerate electronic bands, which can touch at so-called Weyl points. The spinor eigenstates in the vicinity of…
Helical Topological Superconducting Pairing at Finite Excitation Energies
Masoud Bahari, Song-Bo Zhang, Chang-An Li +4
We propose helical topological superconductivity away from the Fermi surface in three-dimensional time-reversal-symmetric odd-parity multiband superconductors. In these systems, pa…
Classification of Weyl points and nodal lines based on magnetic point groups for spin- quasiparticles
Andy Knoll, Carsten Timm
Symmetry-protected topological semimetals are at the focus of solid-state research due to their unconventional properties, for example, regarding transport. By investigating local…
Dynamical density and spin response of Fermi arcs and their consequences for Weyl semimetals
Sayandip Ghosh, Carsten Timm
Weyl semimetals exhibit exotic Fermi-arc surface states, which strongly affect their electromagnetic properties. We derive analytical expressions for all components of the composit…
Negative longitudinal magnetoconductance at weak fields in Weyl semimetals
Andy Knoll, Carsten Timm, Tobias Meng
Weyl semimetals are topological materials that provide a condensed-matter realization of the chiral anomaly. A positive longitudinal magnetoconductance quadratic in magnetic field…
Time-convolutionless master equation: Perturbative expansions to arbitrary order and application to quantum dots
Konstantin Nestmann, Carsten Timm
The time-convolutionless quantum master equation is an exact description of the nonequilibrium dynamics of open quantum systems, with the advantage of being local in time. We deriv…
Multiband Effects in Equations of Motion of Observables Beyond the Semiclassical Approach
Troy Stedman, Carsten Timm, Lilia M. Woods
The equations of motion for the position and gauge invariant crystal momentum are considered for multiband wave packets of Bloch electrons. For a localized packet in a subset of ba…
Charge-spin response and collective excitations in Weyl semimetals
Sayandip Ghosh, Carsten Timm
Weyl semimetals are characterized by unconventional electromagnetic response. We present analytical expressions for all components of the frequency- and wave-vector-dependent charg…
Electron-hole pairing of Fermi-arc surface states in a Weyl-semimetal bilayer
Paolo Michetti, Carsten Timm
The topological nature of Weyl semimetals (WSMs) is corroborated by the presence of chiral surface states, which connect the projections of the bulk Weyl points by Fermi arcs (FAs)…
Violation of Onsager's theorem in approximate master equation approaches
Kevin Marc Seja, Gediminas Kiršanskas, Carsten Timm +1
The consistency with Onsager's theorem is examined for commonly used perturbative approaches, such as the Redfield and second-order von Neumann master equations, for thermoelectric…
Interrupted orbital motion in density-wave systems
Maxim Breitkreiz, Philip M. R. Brydon, Carsten Timm
In conventional metals, electronic transport in a magnetic field is characterized by the motion of electrons along orbits on the Fermi surface, which usually causes an increase in…
Interaction-Induced Renormalization of Tunneling into Multiple Majorana End States of a Topological Superconducting Wire
Oleksiy Kashuba, Carsten Timm
We investigate a system of multiple Majorana states at the end of a topological superconducting wire coupled to a normal lead. For a minimum of three Majorana fermions at the inter…
Transport in multiband systems with hot spots on the Fermi surface: Forward-scattering corrections
Maxim Breitkreiz, P. M. R. Brydon, Carsten Timm
Multiband models with hot spots are of current interest partly because of their relevance for the iron-based superconductors. In these materials, the momentum-dependent scattering…
Spin-charge disparity of polarons in organic ferromagnets
G. C. Hu, H. Wang, J. F. Ren +2
Polaron formation in quasi-one-dimensional organic ferromagnets is studied based on an extended Su-Schrieffer-Heeger model combined with a Kondo term. The charge distribution of th…
Transport anomalies due to anisotropic interband scattering
Maxim Breitkreiz, P. M. R. Brydon, Carsten Timm
Unexpected transport behavior can arise due to anisotropic single-particle scattering in multiband systems. Specifically, we show within a semiclassical Boltzmann approach beyond t…
Spectroscopy of the transition-rate matrix for molecular junctions: dynamics in the Franck-Condon regime
Agnieszka Donabidowicz-Kolkowska, Carsten Timm
The quantum master equation applied to electronic transport through nanoscopic devices provides information not only on the stationary state but also on the dynamics. The dynamics…
Memristive properties of single-molecule magnets
Carsten Timm, Massimiliano Di Ventra
Single-molecule magnets weakly coupled to two ferromagnetic leads act as memory devices in electronic circuits---their response depends on history, not just on the instantaneous ap…
Transport through a quantum spin Hall quantum dot
Carsten Timm
Quantum spin Hall insulators, recently realized in HgTe/(Hg,Cd)Te quantum wells, support topologically protected, linearly dispersing edge states with spin-momentum locking. A loca…
Cotunneling through a magnetic single-molecule transistor based on N\atC60
Nicolas Roch, Romain Vincent, Florian Elste +4
We present an experimental and theoretical study of a magnetic single-molecule transistor based on N@C60 connected to gold electrodes. Particular attention is paid to the regime of…
Time-convolutionless master equation for quantum dots: Perturbative expansion to arbitrary order
Carsten Timm
The master equation describing the non-equilibrium dynamics of a quantum dot coupled to metallic leads is considered. Employing a superoperator approach, we derive an exact time-co…
Noise Spectra of ac-driven quantum dots
B. H. Wu, C. Timm
We study the transport properties of a quantum dot driven by either a rotating magnetic field or an ac gate voltage using the Floquet master-equation approach. Both types of ac dri…
Resonant and Kondo tunneling through molecular magnets
Florian Elste, Carsten Timm
Transport through molecular magnets is studied in the regime of strong coupling to the leads. We consider a resonant-tunneling model where the electron spin in a quantum dot or mol…
Tunneling Spectra of Individual Magnetic Endofullerene Molecules
Jacob E. Grose, Eugenia S. Tam, Carsten Timm +6
The manipulation of single magnetic molecules may enable new strategies for high-density information storage and quantum-state control. However, progress in these areas depends on…
Tunneling through molecules and quantum dots: master-equation approaches
Carsten Timm
An important class of approaches to the description of electronic transport through molecules and quantum dots is based on the master equation. We discuss various formalisms for de…