Quantum fluctuations in two-dimensional systems

Abstract

The influence of quantum effects on properties of two-dimensional systems which are equivalent to the plane quantum rotator model is considered. The expression for the vortex partition function for two-dimensional quantum systems is obtained. The authors study the correlation function of the system and analyse the crossover, i.e. a change of the effective dimensionality of the correlation function behaviour with quantum parameter variation. The dependence of the transition temperature on the quantum parameter is found.