Fluctuations in the interface between two phases

Abstract

In continuation of an earlier paper [F. Schl\"ogl and R. S. Berry, Phys. Rev. A 21, 2078 (1980)] (referred to as I), small fluctuations in the interface between two phases will be discussed and with this an error in I will be corrected. The dynamics of the fluctuations is connected with the quantum mechanics of the modified P\"oschl-Teller potential. Moreover, the fluctuations in the solitary solution of a moving surface are studied and also brought into connection with a quantum-mechanical system. The regression spectrum of these fluctuations is discussed in dependence on the velocity of the interface. If this velocity exceeds a certain value, the character of the regression to the kink profile changes qualitatively.