Polarization-independent intersubband based GaInAsN quantum-well photodetector with dominant detection at 1.42 μm

We report on a room temperature polarization-independent intersubband photocurrent (PC) in quantum-well infrared photodetector based on a GaInAsN/GaAs standard multiple-quantum-well structure. The dominant room temperature PC is peaked at 1.42 μm with peak responsivity of 2 A/W and exhibits similar intensities in TM and TE polarizations. The structure's energy levels were analyzed using a ten band k·p model. As a result of this analysis the 1.42 μm dominant PC transition is attributed to a transition from the fundamental E_1- electron level into the localized quasicontinuum state formed by the unconfined E₂₊ electron energy level.