Phonon blocking by two dimensional electron gas in polar CdTe/PbTe heterojunctions

Abstract

Narrow-gap lead telluride crystal is an important thermoelectric and mid-infrared material in which phonon functionality is a critical issue to be explored. In this Letter, efficient phonon blockage by forming a polar CdTe/PbTe heterojunction is explicitly observed by Raman scattering. The unique phonon screening effect can be interpreted by recent discovery of high-density two dimensional electrons at the polar CdTe/PbTe(111) interface which paves a way for design and fabrication of thermoelectric devices.