97-14E
97-14E
Soft Mode in Locally Anharmonic "$\varphi ^3+\varphi ^4$" Model.
The dynamics of collective vibrations in the locally anharmonic model is studied. The single ion problem is treated by numerical calculation while interaction between ions in different cells is accounred for in the random phase approximation. The density of vibrational states is obtained at various values of the temperature, single ion asymmetry field and wave vector. The existence in the spectrum of the soft mode which energy comes to zero at the critical point is verified. The redistribution of intensities among various energy branches as the wave vector varies is studied.