Nonradiative carrier recombination processes of n-Hg1−xCdxTe as determined by magnetic quantum oscillations

Abstract

A mew method to determine the dominant process of nonradiative carrier recombination is proposed and demonstrated for n-Hg1−xCdxTe (x≂0.2). This method is an application of the magnetic quantum oscillations of high electric field magnetoresistance which were observed successfully in a wide temperature range from 4.2 to 100 K by using a pulse technique and a second derivatives method, where Shockley–Read recombination as well as Auger recombination could be observed as an oscillatory behavior. The dominant origins of the oscillations could be clearly determined from the temperature dependence of the peak positions. Measurement and analysis were performed for a variety of samples with various carrier concentrations n and various electron mobilities μH (n=3×1014–2×1015 cm−3, μH=8×103–3×105 cm2/V s at 4.2 K). A competitive behavior of Shockley–Read and Auger processes and its sample dependence were clearly demonstrated.