Intersubband transition in p-type wurtzite GaN/AlGaN quantum well

The intersubband (ISB) transition of wurtzite (WZ) p-type GaN/AlGaN quantum well (QW) structures was investigated as a function of Al content in barrier using the multiband effective-mass theory. The peak wavelength of the TE-polarization absorption spectrum is rapidly redshifted with decreasing Al content in the barrier. The peak intensity of the TE-polarization absorption spectrum is shown to be similar to that of the TM-polarization absorption spectrum. We find that the peak wavelength of the TE-polarized absorption spectrum of 1.55 μm is possible even for the QW structure with a small Al content of x=0.7. We expect that a p-type WZ GaN/AlGaN heterostructure is attractive for a photodetector application for fiber-optic communications.