Taking advantage of light- and heavy-hole trions for optical spin initialization, control and readout

TL;DR

This paper introduces the use of light-hole trions in semiconductor nanostructures for enhanced optical spin initialization, control, and readout, complementing heavy-hole trions and enabling more efficient quantum operations.

Contribution

It demonstrates the potential of light-hole trions for all single qubit operations and provides experimental evidence of their existence and utility in GaAs nitrogen pairs.

Findings

Light-hole trions enable all single qubit operations in a compatible magnetic field.

Experimental confirmation of light- and heavy-hole excitons and trions in GaAs nitrogen pairs.

Trion states offer a lambda level structure for fast initialization and single-shot readout.

Abstract

Optical control strategies in semiconductor nanostructures have almost exclusively relied on heavy-hole exciton and trion states. In the first part of this letter, we show that light-hole trions provide the missing ressource for consolidating all single qubit operations in a mutually compatible magnetic field configuration: electron spin initialization and control can be achieved through light-hole trion states and cycling transition is provided by heavy-hole trion states. In the second part, we experimentally demonstrate that pairs of nitrogen atoms in GaAs exhibiting a Cs symmetry bind both light- and heavy-hole excitons and negative trions. A detailed analysis of the fine structure reveals that that trion states provide the lambda level structure necessary for fast initialization and control along with energetically-protected cycling transition compatible with single-shot readout.