Resonant and relaxation absorption of ultrasound by anisotropic Jahn-Teller centers in GaAs

Abstract

The contribution of the Jahn-Teller effect to absorption of an ultrasonic wave by a GaAs crystal doped with copper has been investigated theoretically. The distinguishing feature of the problem under con sideration is the existence of two holes in the state of the complex valence band. The magnitude of the tun neling splitting in Jahn-Teller centers has been determined. The theoretical values of the absorption coeffi cients for the resonant and relaxation types of absorption have been obtained. The magnitudes of these coef ficients have been estimated.

Effect of Ultrasonic Treatment on the Properties of Pyrophyllite and Thermodynamic and Kinetic Regularities of its Intercalation with Lithium

“…It has "guest" positions required for intercalation and located between weakly connected aluminosilicate layers [2]. Polymorphism, isovalent isomorphism [3,4], and impurities (together with weak bonds between the layers) typical of pyrophyllite make it suitable for the efficient modification by ultrasonic irradiation [5][6][7][8], which belongs to possible and safe production-and-technological operations. In the literature, there is no information about the influence of ultrasound on the thermodynamic and kinetic properties of pyrophyllite important for the intercalation current formation.…”