Photo electromotive force in CdTe:Ge: manifestation of two photorefractive centers

• Published in: Applied physics. B, Lasers and optics Vol. 99; no. 4; pp. 701 - 707
• Main Authors: dos Santos, T. O., Frejlich, J., Shcherbin, K.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.06.2010; Springer
• Subjects: Diffusion length; Electric potential; Engineering; Exact sciences and technology; Frames; Frequency ranges; Frequency response; Fundamental areas of phenomenology (including applications); Lasers; Optical Devices; Optical materials; Optics; Other nonlinear optical materials; photorefractive and semiconductor materials; Photonics; Physical Chemistry; Physics; Physics and Astronomy; Quantum Optics; Semiconductors; Wavelengths; Grating Formation; Grating Spacing; Spatial Frequency; Reference Beam; Debye Screening Length; Cadmium Tellurides; Charge carriers; Photorefractive materials; Space charge; Doped materials; Binary compounds; Electromotive force; Frequency response; Germanium additions
• ISSN: 0946-2171; 1432-0649
• DOI: 10.1007/s00340-010-3921-1

The photo-electromotive-force effect in CdTe:Ge is studied. A nontrivial frequency response with two different cutoff frequencies is found in the sample studied when exposed to 1064 nm wavelength. The experimental results reveal that two photorefractive centers with charge carriers of the same sign participate in the space-charge formation. The data for different frequency ranges are analyzed individually in the frame of a one-level model for monopolar semiconductor. The photorefractive centers important at different frequency ranges are associated with two species known for CdTe:Ge. Two values for the diffusion length evaluated from the experimental data are linked to these centers.