High fidelity all-optical control of quantum dot spins: detailed study of the adiabatic approach

TL;DR

This paper demonstrates that all-optical adiabatic control of quantum dot spins can achieve high-fidelity single-qubit phase gates that are robust against decoherence and feasible with current experimental setups.

Contribution

It introduces an all-optical adiabatic method for quantum dot spin control that offers high fidelity and robustness with minimal resource requirements.

Findings

Achieves a fidelity of 0.999 at finite temperature.

Gate duration is comparable to dynamic methods, within an order of magnitude.

Experimental implementation is feasible with modest resources.

Abstract

Confined electron spins are preferred candidates for embodying quantum information in the solid state. A popular idea is the use of optical excitation to achieve the ``best of both worlds'', i.e. marrying the long spin decoherence times with rapid gating. Here we study an all-optical adiabatic approach to generating single qubit phase gates. We find that such a gate can be extremely robust against the combined effect of all principal sources of decoherence, with an achievable fidelity of 0.999 even at finite temperature. Crucially this performance can be obtained with only a small time cost: the adiabatic gate duration is within about an order of magnitude of a simple dynamic implementation. An experimental verification of these predictions is immediately feasible with only modest resources.