Interband tansition and electronic structures in strained In_xGa_1-xN/GaN multiple quantum well

In_xGa_1-xN/GaN multiple quantum wells (MQWs), composed of 28-Å In_0.29Ga_0.71N wells and 24-Å In_0.23Ga_0.77N wells, were grown by using metal-organic chemical vapor deposition. Temperaturedependent photoluminescence (PL) spectra showed that the energies of the two dominant peaks in the In_xGa_1-xN/GaN MQWs decreased with increasing temperature. The electronic subband energies and the wavefunctions in the In_xGa_1-xN/GaN MQWs were calculated by solving the Schrödinger equation in the 8-band envelope function approximation. The effects of the spontaneous polarization, strain and piezoelectric polarizations on the electronic structures of the In_xGa_1-xN/GaN MQWs were examined to explain the PL data. The calculated interband transition energies from the ground electronic subbands to the ground hole subbands in In_xGa_1-xN/GaN MQWs were in reasonable agreement with those obtained from the PL spectra.