Time-resolved and excitation-dependent photoluminescence study of CdTe/MgCdTe double heterostructures grown by molecular beam epitaxy

This Letter reports the optical properties of CdTe/MgCdTe double heterostructures grown by molecular beam epitaxy. Low-temperature photoluminescence shows strong band-to-band emission and very weak defect related peaks, indicating low defect densities. The measured Shockley-Read-Hall lifetimes range from 57 to 86 ns at room temperature for samples grown under different conditions. The material radiative recombination coefficient B in the recombination rate defined as R = A Delta n + (1 - gamma)B Delta n(2) + C Delta n(3) [Wang et al., Phys. Status Solidi B 244, 2740 (2007)] is evaluated to be 4.360.5 +/- 10(-9) cm(3).s(-1) with a photon recycling factor gamma of 0.85 calculated based on the geometric structure of the samples. (c) 2014 American Vacuum Society.