312 citations · 5.8k across the 176 of their papers we have counts for
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Semiclassical Theory for Decay and Fragmentation Processes in Chaotic Quantum Systems
Martha Gutierrez, Daniel Waltner, Jack Kuipers +1
We consider quantum decay and photofragmentation processes in open chaotic systems in the semiclassical limit. We devise a semiclassical approach which allows us to consistently ca…
The semiclassical continuity equation for open chaotic systems
Jack Kuipers, Daniel Waltner, Martha Gutierrez +1
We consider the continuity equation for open chaotic quantum systems in the semiclassical limit. First we explicitly calculate a semiclassical expansion for the probability current…
Interplay between quantum dissipation and an in-plane magnetic field in the spin ratchet effect
Sergey Smirnov, Dario Bercioux, Milena Grifoni +1
We investigate the existence of the pure spin ratchet effect in a dissipative quasi-one-dimensional system with Rashba spin-orbit interaction. The system is additionally placed int…
Symmetry Classes in Graphene Quantum Dots: Universal Spectral Statistics, Weak Localization, and Conductance Fluctuations
J. Wurm, A. Rycerz, I. Adagideli +3
We study the symmetry classes of graphene quantum dots, both open and closed, through the conductance and energy level statistics. For abrupt termination of the lattice, these prop…
Optimal block-tridiagonalization of matrices for coherent charge transport
Michael Wimmer, Klaus Richter
Numerical quantum transport calculations are commonly based on a tight-binding formulation. A wide class of quantum transport algorithms requires the tight-binding Hamiltonian to b…
Charge-memory effect in a polaron model: equation-of-motion method for Green functions
Pino D'Amico, Dmitry A. Ryndyk, Gianaurelio Cuniberti +1
We analyze a single-level quantum system placed between metallic leads and strongly coupled to a localized vibrational mode, which models a singlemolecule junction or an STM setup.…
Semiclassical Mechanism for the Quantum Decay in Open Chaotic Systems
Daniel Waltner, Martha Gutierrez, Arseni Goussev +1
We address the decay in open chaotic quantum systems and calculate semiclassical corrections to the classical exponential decay. We confirm random matrix predictions and, going bey…
Diffusion and localization in carbon nanotubes and graphene nanoribbons
Norbert Nemec, Klaus Richter, Gianaurelio Cuniberti
We study transport length scales in carbon nanotubes and graphene ribbons under the influence of Anderson disorder. We present generalized analytical expressions for the density of…
Spin-polarized tunneling through randomly transparent magnetic junctions: Reentrant magnetoresistance approaching the Julliere limit
Grigory Tkachov, Klaus Richter
Electron conductance in planar magnetic tunnel junctions with long-range barrier disorder is studied within Glauber-eikonal approximation enabling exact disorder ensemble averaging…
Coherent backscattering of Bose-Einstein condensates in two-dimensional disorder potentials
Michael Hartung, Thomas Wellens, Cord A. Mueller +2
We study quantum transport of an interacting Bose-Einstein condensate in a two-dimensional disorder potential. In the limit of vanishing atom-atom interaction, a sharp cone in the…
Loschmidt echo for local perturbations: non-monotonous cross-over from the Fermi-golden-rule to the escape-rate regime
Arseni Goussev, Daniel Waltner, Klaus Richter +1
We address the sensitivity of quantum mechanical time evolution by considering the time decay of the Loschmidt echo (LE) (or fidelity) for local perturbations of the Hamiltonian. W…
Spin-polarized Quantum Transport in Mesoscopic Conductors: Computational Concepts and Physical Phenomena
Michael Wimmer, Matthias Scheid, Klaus Richter
Mesoscopic conductors are electronic systems of sizes in between nano- and micrometers, and often of reduced dimensionality. In the phase-coherent regime at low temperatures, the c…
Quantum dissipative Rashba spin ratchets
Sergey Smirnov, Dario Bercioux, Milena Grifoni +1
We predict the possibility to generate a finite stationary spin current by applying an unbiased ac driving to a quasi-one-dimensional asymmetric periodic structure with Rashba spin…
Charge-memory polaron effect in molecular junctions
Dmitry A. Ryndyk, Pino D'Amico, Gianaurelio Cuniberti +1
The charge-memory effect, bistability and switching between charged and neutral states of a molecular junction, as observed in recent STM experiments, is considered within a minima…
Random Wave Functions with boundary and normalization constraints: Quantum statistical physics meets quantum chaos
Juan Diego Urbina, Klaus Richter
We present an improved version of Berry's ansatz able to incorporate exactly the existence of boundaries and the correct normalization of the eigenfunction into an ensemble of rand…