CORRELATIONS BETWEEN MICROSCOPIC PROPERTIES AND THE PHOTOREFRACTIVE RESPONSE FOR VANADIUM-DOPED CDTE

We present a summary of the experimental results, the attempts of inte rpretation at the present stage, and the conclusions of coupled invest igations on semi-insulating, n-type and p-type vanadium-doped CdTe cry stals. Combining electron paramagnetic resonance and magnetic circular dichroism permits the monitoring and the quantitative assessment of [ V2+] and [V3+] defect concentrations. Photoabsorption results are pres ented and are discussed in terms of photoionization processes at vario us wavelengths. The temperature and the spectral dependence of the ste ady-state photoconductivity are carefully studied in the near infrared . The results are discussed in terms of electronic transitions for the two vanadium charge states. Finally, the photorefractive performances of the semi-insulating sample are analyzed in a two-beam-coupling exp eriment and are correlated to the properties of the V2+/V3+ donor stat es to derive photoionization cross sections. (C) 1996 Optical Society of America.