Warm electron effects in narrow gap Hg1-xCdxTe alloys at ambient temperatures

The predominant scattering mechanism controlling the electrical conductivity of Hg 1-x Cd x Te alloys is not fully understood in the temperature range 100-400K. Results are reported at 295K for two narrow gap alloys (x=0.20, 0.22) on high field galvanomagnetic effects and warm electron effects for which a novel measurement technique is described. The galvanomagnetic results are consistent with predominant polar optical mode scattering. The warm electron coefficient, beta , was measured to be much larger than can be explained by this mechanism alone or in combination with electron-heavy hole scattering. An effective beta value associated with changes in the Auger recombination and generation rates has been estimated and also shown to be smaller than the measured values.