Photoluminescence determination of well depth ofGa0.47In0.53As/Al0.48In0.52As in an ultrathin single quantum well

The photoluminescence spectra were measured from 4 to 90 K for single-quantum-well structures of (Ga,In)As/(Al, In)As with well widths $L_z$=14.5 and 19.3 Å. The optical transitions were observed from n=1 electrons in the conduction-band well to n=1 heavy holes (hh) and light holes (lh) in the valence-band well. Using the observed energy separation between hh and lh subbands, the well depth Δ$E_v$=120 meV for holes in the valence band and the corresponding well depth Δ$E_c$=740 meV for electrons in the conduction band were determined. This gives the relation of Δ$E_c$=0.85Δ$E_g$ which agrees with Dingle’s rule for GaAs/(Al,Ga)As system.