Luxemburg-gorky effect retooled for elastic waves: a mechanism and experimental evidence

A new mechanism is proposed for the linear and amplitude-dependent dissipation due to elastic-wave-crack interaction. We have observed one of its strong manifestations in a direct elastic-wave analog of the Luxemburg-Gorky effect consisting of the cross modulation of radio waves at the dissipative nonlinearity of the ionosphere plasma. The counterpart acoustic mechanism implies, first, a drastic enhancement of the thermoelastic coupling at high-compliance microdefects, and, second, the high stress-sensitivity of the defects leads to a strong stress dependence of the resultant dissipation.