Observation of the quantum-confined Stark effect in a GaAs/AlGaAs p-i-n diode by room temperature photocurrent spectroscopy
Abstract
Room temperature photocurrent spectroscopy is performed on an MBE-grown GaAs/AlGaAs multiple quantum well (MQW) p-i-n device. An observed shift to longer wavelengths is seen with increasing reverse bias voltages. This behavior is explained through a mechanism called the quantum-confined Stark effect. Applied electric fields are estimated using second-order correction for infinite quantum wells. The estimated built-in electric field is 20kV/cm corresponding to a 9 meV shift from the flatband energy transition. An observed shift to shorter wavelengths is seen under an optically applied field for both biased and unbiased conditions.