Photocurrent oscillations in GaInNAs / GaAs multi-quantum well p-i-n structures

In this work the photoconductivity of a p-i-n Ga
_0.952
In
_0.048
N
_0.016
As
_0.984
/GaAs multiple quantum well (MQW) structure is investigated as a function of temperature. At low temperatures step-like increases are observed in the devices I-V characteristic when illuminated with a 950nm wavelength light. The number of visible oscillations varies according to the temperature and incident light intensity with a maximum of 18 being visible. Since the exciting illumination energy is bellow the GaAs bandgap, these oscillations arise only from the GaInNAs quantum wells and can be explained in terms of resonant tunneling from subbands into the adjacent quantum well.