English

Simulation of 1/f charge noise affecting a quantum dot in a Si/SiGe structure

Mesoscale and Nanoscale Physics 2024-08-09 v2 Quantum Physics

Abstract

Due to presence of magnetic field gradient needed for coherent spin control, dephasing of single-electron spin qubits in silicon quantum dots is often dominated by 1/f1/f charge noise. We investigate theoretically fluctuations of ground state energy of an electron in gated quantum dot in realistic Si/SiGe structure. We assume that the charge noise is caused by motion of charges trapped at the semiconductor-oxide interface. We consider a realistic range of trapped charge densities, ρ ⁣ ⁣1010\rho \! \sim \! 10^{10} cm2^{-2}, and typical lenghtscales of isotropically distributed displacements of these charges, δr ⁣ ⁣1\delta r \! \leq \! 1 nm, and identify pairs (ρ,δr)(\rho,\delta r) for which the amplitude and shape of the noise spectrum is in good agreement with spectra reconstructed in recent experiments on similar structures.

Keywords

Cite

@article{arxiv.2303.13968,
  title  = {Simulation of 1/f charge noise affecting a quantum dot in a Si/SiGe structure},
  author = {Marcin Kępa and Niels Focke and Łukasz Cywiński and Jan. A. Krzywda},
  journal= {arXiv preprint arXiv:2303.13968},
  year   = {2024}
}

Comments

5 pages, 5 figures, added repository: https://doi.org/10.24435/materialscloud:mx-0w