Властивості квадрупольної фази двовимірного кулонівського газу

Abstract

Peculiarities of the internal thermal excitations of quadrupole clusters in a two-dimensional Coulombic gas are investigated. It is shown that, among five modes of excitations, three modes are soft, and two ones have hard character. One of the soft modes is harmonic, and two ones are determined by quadratic forces. The partial case of harmonic oscillations - the so-called contact ones - is studied in detail. It is established that the characteristic temperature for the disintegration of quadrupole clusters is practically coincided with the Kosterlitz-Thouless temperature.