Magnetic Field-Dependent Overhauser Field Hysteresis Produced by Periodic Optical Pumping and Directionally Sweeping the Magnetic Field*

Optically pumping the electron spin system in semiconductors is known to polarize the nuclear spins through a process known as dynamic nuclear polarization. The dynamic polarization of the nuclear spins will cause the nuclei to build up an intrinsic magnetic field, which is commonly referred to as the Overhauser field. This Overhauser field can be monitored through its effect on the electron spin precession frequency [1]. Under periodic optical pumping with a repetition period of 6.5 ns [2], the Overhauser field has been observed to exhibit hysteretic behavior, in which the steady-state Overhauser field depends on the magnetic field history [3]. The presented model demonstrates that bistable solutions to the Overhauser field give rise to the Overhauser hysteresis, and numerical modeling predicts the resulting electron and nuclear spin dynamics attributed to the Overhauser hysteresis. One manifestation of the Overhauser hysteresis is the existence of two different discrete electron spin precession frequencies for a given external magnetic field.

[1] M. J. Dominguez, H.-W. Hsu, and V. Sih, Phys. Rev. B 108, 115203 (2023)

[2] E. Kesto, M. J. Dominguez, and V. Sih, J. Appl. Phys. 133, 193901 (2023)

[3] E. Kesto, M. J. Dominguez, and V. Sih, Submitted 09 Oct. 2023