Giant ultrasonic attenuation in ZnSe basic solid state physics doped with Cr and its possible application in crystal characterization

Abstract

Ultrasonic experiment was done at the frequency of 54 MHz on ZnSe:Cr2+ crystal with concentration of the dopand 3.8 × 1018 cm-3. Giant peak of attenuation of slow shear wave propagating along 〈110〉 crystallographic direction was observed at low temperatures (about 13 K). The peak proved to be due to relaxation process in the Jahn-Teller system. Magnitude of the peak is proportional to the concentration of the dopand. This circumstance forms the basis for a new nondestructive method of characterization of the diluted crystals, which particularly could be useful for determining the low concentration of the Jahn-Teller ions. Estimation showed that the concentration of the dopand can be registered in ZnSe:Cr2+ crystal of the order of 1016 cm-3. Other Jahn-Teller ions prospective for such characterization are suggested. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.