English

A spin dephasing mechanism mediated by the interplay between the spin-orbit coupling and the asymmetrical confining potential in semiconductor quantum dot

Mesoscale and Nanoscale Physics 2018-09-12 v2 Quantum Physics

Abstract

Understanding the spin dephasing mechanism is of fundamental importance in all potential applications of the spin qubit. Here we demonstrate a spin dephasing mechanism in semiconductor quantum dot due to the 1/f1/f charge noise. The spin-charge interaction is mediated by the interplay between the spin-orbit coupling and the asymmetrical quantum dot confining potential. The dephasing rate is proportional to both the strength of the spin-orbit coupling and the degree of the asymmetry of the confining potential. For parameters typical of the InSb, InAs, and GaAs quantum dots with a moderate well-height V0=10V_{0}=10 meV, we find the spin dephasing times are T2=7{\rm T}^{*}_{2}=7 μ\mus, 275275 μ\mus, and 5555 ms, respectively. In particular, the spin dephasing can be enhanced by lowering the well-height. When the well-height is as small as V0=5V_{0}=5 meV, the spin depahsing times in the InSb, InAs, and GaAs quantum dots are decreased to T2=0.38{\rm T}^{*}_{2}=0.38 μ\mus, 1818 μ\mus, and 99 ms, respectively.

Keywords

Cite

@article{arxiv.1805.10792,
  title  = {A spin dephasing mechanism mediated by the interplay between the spin-orbit coupling and the asymmetrical confining potential in semiconductor quantum dot},
  author = {Rui Li},
  journal= {arXiv preprint arXiv:1805.10792},
  year   = {2018}
}

Comments

14 pages, 9 figures