Skip to content.

TUD

search  |  internal  |  deutsch
Personal tools
TU Dresden » Faculty of Mechanical Science and Engineering » Institute for Materials Science » Chair of Materials Science and Nanotechnology



Monday, 12 July 2004
(at 16:15 in room H34)
Add to your Google Calendar


Quantum ratchets

Milena Grifoni

Institut für Theoretische Physik
Universität Regensburg
   






Ratchets are periodic structures lacking spatial inversion symmetry. Despite the asymmetry, no preferential motion occurs for particles moving in a ratchet potential and being only subject to equilibrium thermal noise, in agreement with the second law of thermodynamics. However, directed motion can occur under the combined effect of thermal noise and unbiased driving forces.
We investigate this so-called ratchet effect for Brownian particles moving in one-dimensional ratchet structures. We focus on temperatures such that tunnelling is the dominant transport mechanism. We discuss the occurrence of current reversals as the parameters of the bath or of the driving force are varied.
We finally report on the recent experimental observation of the quantum ratchet effect for vortices in quasi one-dimensional arrays of Josephson junctions.

phys. dept. links: abstract(pdf file)



slides (pdf)

Within the Physikalisches Kolloquium SS04

last modified: 2019.01.18 Fr
author: webadmin

contact
Prof. Dr. Gianaurelio Cuniberti
secretariat:
Ms Sylvi Katzarow
phone: +49 (0)351 463-31420
fax: +49 (0)351 463-31422
office@nano.tu-dresden.de
postal address:
Institute for Materials Science
TU Dresden
01062 Dresden, Germany
visitors and courier address:
HAL building
TU Dresden
Hallwachsstr. 3
01069 Dresden, Germany
Max Bergmann Center
TU Dresden
Budapester Str. 27
01069 Dresden, Germany