Charge transfer in photorefractive CdTe:Ge at different wavelengths

• Published in: Optical materials 2001, Vol.18 (1), p.151-154
• Main Authors: Shcherbin, K, Odoulov, S, Ramaz, F, Farid, B, Briat, B, von Bardeleben, H.J, Delaye, P, Roosen, G
• Format: Article
• Language: English
• Subjects: Cadmium telluride; CdTe:Ge; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Optical materials; Optics; Other nonlinear optical materials; photorefractive and semiconductor materials; Photorefractive semiconductors; Physics
• ISSN: 0925-3467; 1873-1252
• DOI: 10.1016/S0925-3467(01)00154-9

The charge transfer processes in photorefractive CdTe:Ge were modeled using the data of optical absorption, magnetic circular dichroism (MCD) and electron paramagnetic resonance (EPR) spectroscopies. Within the developed model the variations in the photorefractive properties of different CdTe:Ge samples are explained by differences in the relative concentrations of donor and trap centers. The existence of two different centers of comparable concentrations, each in two charge states, allows charge redistribution between them and gives rise to optical sensitization of some CdTe:Ge samples for photorefractive recording under an auxiliary illumination. In the present article we follow the proposal of pseudo-3D presentation of light-induced absorption to distinguish the main charge transfer processes at different excitation energies and explain the sensitization of CdTe:Ge for photorefractive recording at 1.06, 1.32 and 1.55 μm by light with appropriate wavelength.