Nuclear spin effects in negatively charged InP quantum dots

TL;DR

This paper investigates how nuclear spin effects, including dynamic nuclear polarization and nuclear spin fluctuations, influence electron spin orientation in negatively charged InP quantum dots, revealing key magnetic field interactions and fluctuation lifetimes.

Contribution

It provides the first detailed analysis of nuclear spin effects on electron spins in InP quantum dots, quantifying hyperfine and fluctuation fields and their impact.

Findings

Hyperfine field B_N of a few mT estimated

Nuclear spin fluctuation field B_f of tens of mT estimated

Nuclear spin fluctuation lifetime around 1 microsecond

Abstract

Effects of both the dynamic nuclear polarization (DNP) created by circularly polarized light and the fluctuations of average nuclear spin in a quantum dot (QD) on the electron spin orientation are studied for singly negatively charged InP QDs. From the dependence of the negative circular polarization of photoluminescence on the applied longitudinal magnetic field, the hyperfine field B_N of a few mT appearing due to DNP and the effective magnetic field B_f of a few tens of mT arising from nuclear spin fluctuations (NSF) are estimated. A lifetime of about 1 microsecond is estimated for NSF.