Hole intersubband transitions in wurtzite and zinc-blende strained AlGaN/GaN quantum wells and its interband interaction dependence

Abstract

Valence intersubband transitions of the wurtzite (WZ) strained AlGaN/GaN quantum wells are examined theoretically and compared with those of the zinc-blende (ZB) ones. In particular, the effect of the interband interaction between conduction (CB) and valence (VB) bands has been taken into account explicitly. We have used the 8-bands k.p model for both WZ and ZB structures to calculate subband energies and wavefunctions of Al 0.3 Ga 0.7 N/GaN quantum wells (QWs). The results indicate that, the prominent transitions for both ZB and WZ QWs were found to be essentially related to the heavy- and light-hole subbands. For the x-polarization, we have shown that it is necessary to take into account explicitly the interband interaction between CB and VB. Finally, we can predict that WZ QWs are more convenient than ZB QWs in most applications involving intersubband transitions, especially for the z-polarized light.