Solution‐Processed Ion‐Free Organic Ratchets with Asymmetric Contacts

Asymmetric Weak-Pinning Superconducting Channels: Vortex Ratchets

Dissipation Enhanced Asymmetric Transport in Quantum Ratchets

Quantum mechanical motion of a particle in a periodic asymmetric potential is studied theoretically at zero temperature. It is shown based on semiclassical approximation that the tunneling probability from one local minimum to the next becomes asymmetric in the presence of weak oscillating field, even though there is no macroscopic field gradient in average. Dissipation enhances this asymmetry,...

Brownian ratchets driven by asymmetric nucleation of hydrolysis waves.

We propose a stochastic process wherein molecular transport is mediated by asymmetric nucleation of domains on a one-dimensional substrate, in contrast with molecular motors that hydrolyze nucleotide triphosphates and undergo conformational change. We show that asymmetric nucleation of hydrolysis waves on a track can also result in directed motion of an attached particle. Asymmetrically coopera...

Particle trapping and self-focusing in temporally asymmetric ratchets with strong field gradients

We study the dynamics of a particle whose velocity is a nonlinear, monotonically increasing function of the applied field. The particle moves in a strong field gradient whose intensity and sign vary periodically. We demonstrate that if the field pulses are temporally asymmetric and biased, we can have situations where the particle always migrates towards a stable zero-velocity point. This speci...

Photoconductance of organic single-molecule contacts

J. K. Viljas,1,2,* F. Pauly,1,2 and J. C. Cuevas1,2,3 1Institut für Theoretische Festkörperphysik and DFG-Center for Functional Nanostructures, Universität Karlsruhe, D-76128 Karlsruhe, Germany 2Forschungszentrum Karlsruhe, Institut für Nanotechnologie, D-76021 Karlsruhe, Germany 3Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, E-28049 Madrid, Spain Rece...