ANALOGY OF THE SECOND ORDER PHASE TRANSITION IN QUASI-OPTICAL MICROWAVE CAVITY RESONATOR

In this paper for the first time we have discovered and studied the analogy of the second order phase transition in spheri-cal microwave cavities with heterogeneity in the form of a metal ball. The transition occurs between the state when the ball is sym-metrically disposed relative to the side walls and the state with asymmetric arrangement of the ball. For these states the spectra of oscillations in 8-mm range were measured and on the basis of the obtained data the correlation coefficients of inter-frequency inter-vals were determined. It has been established that an integrable system of spherical symmetric cavity with an inner ball has a cor-relation coefficient close to zero, while for non-integrable systems with asymmetric arrangement of the ball, the correlation coeffi-cient C(1) > 0.2. Phase transition between these states occurs in a narrow range of eccentricity. The dependence of the distribution of inter-frequency intervals on the mean distance between the natural frequencies were determined and it was found that for an integrable system, this dependence is described by the Poisson function, and for non-integrable by Wigner distribution, which is typical for states with repulsion resonance lines and quantum chaos. Thus, it was found that a change in the symmetry of the microwave resonator leads to the second order phase transition, when the system becomes non-integrable cavity and is accompa-nied by quantum chaos.