Sound-induced melting of solid 4He in a superfluid

Abstract Melting of solid 4 He in a superfluid was observed when sound pulses were applied to the surface. Amount of melting was measured by changing the sound power and pulse numbers. It is not proportional to the power but to the square root of it. Both power and pulse number dependences are explained consistently if the melting coefficient is about 10% larger than that of the growth coefficient.