Crystal orientation effect on valence-subband structures in wurtzite-GaN strained quantum wells

We analyze theoretically for the first time valence-subband structures in wurtzite-GaN strained quantum wells (QWs) for various crystal orientations. The calculation is based on the Bir-Pikus effective-mass theory, where deformation potentials are determined by a semi-empirical tight-binding method. The obtained results show that the hole effective masses of strained QWs with non-(0001) orientation, in particular, around the (10*BAR*1*BAR*2) orientation, are markedly lighter than those of (0001) cases. We also found that the optical matrix elements of non-(0001) strained QWs are twice as large as those for (0001) strained QWs.