English

Geometric quantum pumping in the presence of dissipation

Quantum Physics 2014-09-29 v2 Mesoscale and Nanoscale Physics

Abstract

The charge transported when a quantum pump is adiabatically driven by time-dependent external forces in presence of dissipation is given by the line integral of a pumping field F\mathbf{F}. We give a general expression of F\mathbf{F} in terms of quantum correlation functions evaluated at fixed external forces. Hence, an advantage of our method is that it transforms the original time-dependent problem into an autonomous one. Yet another advantage is that the curl of F\mathbf{F} gives immediate visual information about the geometric structures governing dissipative quantum pumping. This can be used in a wide range of experimental cases, including electron pumps based on quantum dots and Cooper-pair pumps based on superconducting devices. Applied to a Cooper-pair sluice, we find an intriguing dissipation-induced enhancement of charge pumping, reversals of current, and emergence of asymmetries. This geometric method thus enables one to unveil a plethora of beneficial, dissipation-assisted operation protocols.

Keywords

Cite

@article{arxiv.1403.3523,
  title  = {Geometric quantum pumping in the presence of dissipation},
  author = {Juzar Thingna and Peter Hänggi and Rosario Fazio and Michele Campisi},
  journal= {arXiv preprint arXiv:1403.3523},
  year   = {2014}
}

Comments

7 pages, 3 figures. v2 accepted by PRB