Stabilizing nuclear spins around semiconductor electrons via the interplay of optical coherent population trapping and dynamic nuclear polarization

TL;DR

This paper demonstrates how optical techniques like coherent population trapping and dynamic nuclear polarization can stabilize nuclear spins around semiconductor electrons, advancing control of spin coherence for quantum technologies.

Contribution

It introduces an experimental method combining CPT and DNP to autonomously stabilize nuclear spin states around donor-bound electrons in GaAs.

Findings

CPT induces autonomous feedback stabilizing nuclear spins.

Tuning laser detuning transitions between one and two stable states.

Spectral CPT features reveal nuclear spin state distributions.

Abstract

We experimentally demonstrate how coherent population trapping (CPT) for donor-bound electron spins in GaAs results in autonomous feedback that prepares stabilized states for the spin polarization of nuclei around the electrons. CPT was realized by excitation with two lasers to a bound-exciton state. Transmission studies of the spectral CPT feature on an ensemble of electrons directly reveal the statistical distribution of prepared nuclear spin states. Tuning the laser driving from blue to red detuned drives a transition from one to two stable states. Our results have importance for ongoing research on schemes for dynamic nuclear spin polarization, the central spin problem and control of spin coherence.