Abstract
We have measured reflected optical second harmonic (SH) intensity from a Cd 1 m; x Zn x Te(1 v; 1 v; 1) ( x =0.045) substrate at the sample temperature of T =9.5 v; K as a function of the incident photon energy E y from 1.55 to 1.65 v; eV. Two resonant peaks at E y =1.59 and 1.61 v; eV were observed. Since the SH peak position of E y =1.61 v; eV is close to those of photoluminescence peaks around ∼1.62 v; eV associated with exciton excitation, the SH peak is tentatively assigned to one-photon resonance of exciton level. The SH intensity at E y =1.61 v; eV drastically decreased when the temperature of the sample was raised above ∼30 v; K. This temperature dependence agrees with that of the exciton luminescence intensity, and strongly supports the above assignment.