Photorefractive gratings formed in a Fe: CdTe crystal by nanosecond laser pulses

摘要

An investigation was made of photorefractive gratings formed by nanosecond laser pulses in an Fe-doped CdTe crystal. Pulsed pumping with the maximum gain Γ=0.3 cm~-1 indu- ced a fast photorefractive effect in this crystal, characterised by a high electron mobility. The orientational dependences of the gain, and its dependences on the grating period and on the in- tensity of the recording radiation, were used to calculate the Debye screening length, the effective concentration of the carrier traps, and other parameters of the investigated crystal, including the ambipolar conditions coefficient taking account of the competition from the minority carriers.