Universal anomalous exponent of photoconduction.
Europhysics Letters, 96(6) article 67007.
Experiments often show that the photoconductance σ of a semiconductor system and the light intensity I are related by σ~Iγ. Conventional theories give a satisfactory explanation for γ=1 or γ=1/2, but anamalous exponents close to γ=3/4 are often observed. This paper argues that there is a universal anomalous regime for which γ=3/4 (or γ=2/3 in two dimensions), resulting from the kinetics of electron-hole recombination being controlled by Coulombic attraction. Because the local electric fields are extremely high, the theory uses the "hot-carrier" model for transport.
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