Optically erasing disorder in semiconductor microcavities with dynamic nuclear polarization

TL;DR

This paper demonstrates that optical pumping can significantly reduce photonic disorder in GaAs microcavities by using nuclear polarization to create an Overhauser field, leading to improved cavity uniformity.

Contribution

It introduces a method of optically erasing disorder in semiconductor microcavities through dynamic nuclear polarization without spatial patterning.

Findings

Photonic disorder reduced by a factor of 100 in GaAs microcavities.

Resonant excitation induces spin-polarized electrons affecting disorder.

Nuclear polarization modifies exciton-polariton potential.

Abstract

The mean squared value of the photonic disorder is found to be reduced by a factor of 100 in a typical GaAs based microcavity, when exposed to a circularly polarized continuous wave optical pump without any special spatial patterning. Resonant excitation of the cavity mode excites a spatially non-uniform distribution of spin-polarized electrons, which depends on the photonic disorder profile. Electrons transfer spin to nuclei via the hyperfine contact interaction, inducing a long-living Overhauser magnetic field able to modify the potential of exciton-polaritons.