Effect of built-in electric field on electron Raman scattering in InGaN/GaN coupled quantum wells

Electron Raman scattering (ERS) in wurtzite In_xGaN_1−x/GaN coupled quantum wells (CQWs) is investigated by effective-mass approximation and second-perturbation approach, including a strong built-in electric field (BEF) effect due to the piezoelectricity and spontaneous polarization. The dependence of differential cross-section (DCS) on structural parameters of CQWs is studied. Our results show that the strong BEF gives rise to a remarkable reduction of the DCS, which is around three orders smaller than that of the CQWs without BEF. With the presence of the BEF, the emitted photon energy decreases about 10 times as a consequence of quantum-confined Stark effect.