Phonon-induced decoherence for a quantum dot spin qubit operated by Raman passage

TL;DR

This paper investigates how phonon interactions affect the fidelity of Raman-based single-qubit gates in quantum dot spin qubits, providing quantitative error estimates and optimal parameters for minimal decoherence.

Contribution

It offers a detailed analysis of phonon-induced errors in Raman passage operations and identifies parameter regimes to minimize such errors in quantum dot systems.

Findings

Error rates can be reduced below 10^{-4} per operation.

Optimal pulse parameters significantly mitigate phonon-induced decoherence.

Quantitative estimates provided for InAs/GaAs quantum dot systems.

Abstract

We study single-qubit gates performed via stimulated Raman adiabatic passage (STIRAP) on a spin qubit implemented in a quantum dot system in the presence of phonons. We analyze the interplay of various kinds of errors resulting from the carrier-phonon interaction as well as from quantum jumps related to nonadiabaticity and calculate the fidelity as a function of the pulse parameters. We give quantitative estimates for an InAs/GaAs system and identify the parameter values for which the error is considerably minimized, even to values below $10^{-4}$ per operation.