Reproduction of single-to-double hysteresis transition of nuclear spin polarization in a single InAlAs quantum dot

Abstract

We have observed a transition from single to double hysteresis of nuclear spin polarization (NSP) with increasing magnetic field in a single InAlAs self-assembled quantum dot, which means the birth of a third stable branch that depends on the field strength. This NSP transition behavior could not be reproduced by standard model calculations using a fixed electron–nuclear spin correlation time τc under different external field conditions. By introducing the field dependence of τc, we were able to successfully reproduce the observed NSP transition. This finding on the phenomenological description of the magnetic field dependence will be a future highlight of τc.