Demonstration of a ¼-cycle phase shift in the radiation-induced oscillatory magnetoresistance in GaAs/AlGaAs devices

Abstract

We examine the phase and the period of the radiation-induced oscillatory magnetoresistance in GaAs/AlGaAs devices utilizing in situ magnetic field calibration by electron spin resonance of diphenyl-picryl-hydrazal. The results confirm a f-independent ¼-cycle phase shift with respect to the hf=jh ω_c condition for j ≥ 1, and they also suggest a small (≈ 2%) reduction in the effective mass ratio, m*/m, with respect to the standard value for GaAs/AlGaAs devices.