Measuring the hole chemical potential in ferromagnetic Ga1−xMnxAs∕GaAs heterostructures by photoexcited resonant tunneling

Abstract

The authors investigate the optical and electrical properties of a p-i-n GaAs∕AlAs resonant tunneling diode in which the p-type layer is the ferromagnetic alloy semiconductor Ga1−xMnxAs (x=3%). The high density of Mn acceptors affects significantly the electrostatic potential profile of the heterostructure and inhibits hole tunneling from Ga1−xMnxAs.The authors use photoconductivity to probe this potential and measure the hole chemical potential in Ga1−xMnxAs relative to the band edges of the adjacent undoped GaAs layers.