Recombination effects in narrow-gap semiconductors p-Hg1−xCdxTe

The recombination characteristics of p-type crystals Hg1–xCdxTe (x=0.195; 0.20) in the temperature range 80 to 300K are investigated. The energetic positions of recombination centres, responsible for recombination in extrinsic temperature range (T ≦ 120 K) are determined from a comparison of experimental and calculated temperature dependences of the charge carrier lifetime. The peculiarities of Auger recombination in p-type Hg1–xCdxTe are studied with respect to the material with n-type conductivity in the intrinsic temperature range (T > 120K). In p-HgCdTe the lifetime-temperature dependence shifts towards higher temperatures with respect to the lifetime-temperature characteristic observed for the intrinsic material. This is in good agreement with the calculation for a semiconductor with different effective masses of electrons and holes. The charge carrier lifetime dependences vs. the level of optical power at λ=10.6 μm in p-HgCdTe are obtained which are characterized by a lifetime increases and subsequent saturation when the optical power increases.