High Pressure Effect On The Dielectric Properties Of Rock-Salt Cds

Using high pressure impedance spectroscopy measurement system, the dielectric property of rock-salt CdS was investigated up to 22.9 GPa. Below 10.0GPa epsilon(r)'' decreased with frequency linearly and epsilon(r)' showed one-step decrease, which was due to the electron hopping transport between impurity levels. From 10.0GPa to 11.6GPa and from 15.8GPa to 22.9 GPa, the one-step decrease of epsilon(r)' with frequency was assigned to the electron transport along one path, from impurity level to Sigma(v) and to L-v, respectively, and the two-step decrease from 11.6GPa to 15.8GPa was caused by the electron transport along the two paths mentioned above. The dielectric constant of CdS grain was calculated and showed w-shape with pressure, which was affected by the pressure induced band structure change. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4729451]