English

Suppression of the Landau-Zener transition probability by a weak classical noise

Mesoscale and Nanoscale Physics 2017-08-23 v1 Quantum Physics

Abstract

When the drive which causes the level crossing in a qubit is slow, the probability, P_{LZ}, of the Landau-Zener transition is close to 1. We show that in this regime, which is most promising for applications, the noise due to the coupling to the environment, reduces the average P_{LZ}. At the same time, the survival probability, 1-P_{LZ}, which is exponentially small for a slow drive, can be completely dominated by noise-induced correction. Our main message is that the effect of a weak classical noise can be captured analytically by treating it as a perturbation in the Schroedinger equation. This allows us to study the dependence of the noise-induced correction to P_{LZ} on the correlation time of the noise. As this correlation time exceeds the bare Landau-Zener transition time, the effect of noise becomes negligible. We consider two conventional realizations of noise: Gaussian noise and telegraph noise.

Keywords

Cite

@article{arxiv.1705.05968,
  title  = {Suppression of the Landau-Zener transition probability by a weak classical noise},
  author = {Rajesh K. Malla and E. G. Mishchenko and M. E. Raikh},
  journal= {arXiv preprint arXiv:1705.05968},
  year   = {2017}
}

Comments

8 pages, 4 figures