Charge carrier governed temperature dependence of the electric field gradient for111Cd in tellurium

Using the TDPAC-method with the proble nucleus¹¹¹Cd the electric quadrupole interaction (QI) in the trigonal semiconductor Te has been investigated in the temperature range 77 KT655 K. In contrast to most metals the quadrupole frequencyv_Q increases with increasing temperature. This is a consequence of the fact that in metals the charge carrier density is temperature independent, whereas in semiconductors it strongly increases with temperature. A comparison between the temperature variation of the quadrupole coupling constantv_Q and that of the charge carrier density leads to the conclusion that the QI in Te is governed by changes in the free electron density.