ABSTRACT
The rock salt cubic semiconductor PbTe material is an iconic thermoelectric system. It has been studied for more than six decades because of its fascinating electronic and thermal transport properties. The material has given the science community many fascinating, intriguing, and even amazing properties to ponder, yet it keeps producing stirring surprises. The pioneering studies on this material began in the 1950s and continued through the 1960s and beyond [1-3]. It was then that many of the fundamental properties were experimentally discovered and theoretically explained. For example, the direct nature of the bandgap, the existence of a second valence band, and the anomalous temperature dependence of the bandgap were documented, and a great deal of the nature of its electronic structure was understood [4-8]. These studies were published in several key papers decades ago [5,6,8].
