Polarization Dependence of Photocurrent in InAs/InGaAs/InP Quantum-Dot Infared Photodetectors

Through polarization dependence measurements of photocurrent together with theoretical calculations we were able to identify different intersubband transitions in InAs/InGaAs/InP quantum dot structures for mid infrared photodetectors. Photocurrent for normal incidence was observed but stronger signals are detected for TM polarization of the incident light, revealing a certain extent of a 2D behavior.