New mechanism for nonlinear sound absorption in metallic glasses
Gal'perin Yu. M. , Gurevich V. L. , Parshin D. A.
An explanation is offered for the frequency and temperature dependences observed for the nonlinear sound absorption in a metallic glass in experiments reported elsewhere. With increasing sound intensity the resonant absorption gives way to a relaxation absorption. The latter becomes nonlinear when the characteristic strain-induced change in the energy of two-level systems becomes greater than kT.