相关论文: Quantum ratchet effect for vortices

Breaking time-reversal symmetry (TRS) in the absence of a net bias can give rise to directed steady-state non-equilibrium transport phenomena such as ratchet effects. Here we present, theoretically and experimentally, the concept of a…

We construct numerically static vortex solutions in a holographic model of two-band superconductor with an interband Josephson coupling in both the superfluid and superconductor regime. We investigate the effects of the interband coupling…

We analyze the dynamics of Brownian ratchets in a confined environment. The motion of the particles is described by a Fick-Jakobs kinetic equation in which the presence of boundaries is modeled by means of an entropic potential. The cases…

Competition between the vortex lattice and a lattice of asymmetric artificial defects is shown to play a crucial role in ratchet experiments in superconducting films. We present a novel and collective mechanism for current reversal based on…

A mechanism to modify the energy band structure is proposed by considering a chain of periodic scatterers forming a linear lattice around which an external cylindrical trapping potential is applied along the chain axis. When this trapping…

In this study, we describe the ratchet transport of particles under static asymmetric potential with periodicity. Ratchet transport has garnered considerable attention due to its potential for developing smart transport techniques on a…

We investigate a two-component, cylindrical, quasi-one-dimensional quantum plasma subjected to a {\em radial} confining harmonic potential and an applied magnetic field in the symmetric gauge. It is demonstrated that such a system as can be…

The quantum Hall effect is a remarkable manifestation of quantized transport in a two-dimensional electron gas. Given its technological relevance, it is important to understand its development in realistic nanoscale devices. In this work we…

Dislocations and disclinations in a lattice of Josephson junctions will affect the dynamics of vortex excitations within the array. These defects effectively distort the space in which the excitations move and interact. The interaction…

We study the crossover between classical and quantum dynamics by observing the behavior of a quantum ratchet created by exposing a Bose-Einstein condensate to short pulses of a potential which is periodic in both space and time. Such a…

We investigate the transport properties of a new class of ratchets. The device is constructed by applying an ac voltage to the metallic single electron tunneling transistor, and a net transport current is induced by the time-dependent…

Ratchet effect, observed in many systems starting from living organism to artificially designed device, is a manifestation of motion in asymmetric potential. Here we report results of a conductivity study of Polypyrrole nanowires, which…

Radiation-induced ratchet electric currents have been studied theoretically in graphene with a periodic noncentrosymmetric lateral potential. The ratchet current generated under normal incidence is shown to consist of two contributions, one…

The directed transport of an overdamped Brownian motor moving in a spatially periodic potential that lacks reflection symmetry (i.e. a ratchet potential) is studied when driven by thermal and dichotomic nonequilibrium noise in the presence…

Transport properties of overdamped Brownian paricles in a rocked thermal ratchet with space dependent friction coefficient is studied. By tuning the parameters, the direction of current exhibit multiple reversals, both as a function of the…

The geometry of optical lattices can be engineered allowing the study of atomic transport along paths arranged in patterns that are otherwise difficult to probe in the solid state. A question readily accessible to atomic systems is related…

We study the equilibrium states of a vortex in a Bose-Einstein condensate in a one-dimensional optical lattice. We find that quantum effects can be important and that it is even possible for the vortex to be strongly squeezed, which…

We calculate non-perturbatively the inelastic effects on the conductance through a conjugated molecular wire-metal heterojunction, including realistic electron-phonon coupling. We show that at sub-band-gap energies the current is dominated…

We propose a scheme for producing directed motion in a lattice system by applying a periodic driving potential. By controlling the dynamics by means of the effect known as coherent destruction of tunneling, we demonstrate a novel…

We present a perturbative study of the response of cold atoms in an optical lattice to a weak time- and space-asymmetric periodic driving signal. In the noninteracting limit, and for a finite set of resonant frequencies, we show how a…