Spectral Oscillation of Impurity Photoconductivity and the Photo-Hall Effect inp-Type InSb

Abstract

Photoconductivity and the photo-Hall effect associated with the impurity in $p$-type InSb were studied with applied magnetic fields up to 8 kG, in the temperature range 5-∼20°K. Both showed a similar oscillation with wavelength, but the magnitude of oscillation was different. A wavelength dependence of Hall mobility was deduced. The effect of the strength of magnetic field was investigated. The normal conductivity of one type of samples studied was dominated by free holes generated by background radiation and thermal ionization. In the second type of samples at 5°K, the Hall coefficient was strongly influenced by free holes but the conductivity was determined chiefly by impurity-band conduction. The results show that a mobility variation was mainly responsible for the oscillation of photoconductivity in the second type of samples at 5°K. The conclusion could be true in the other cases also, according to the results, but it was not proven definitely.