PHYSICS AND MATHEMATICS

Phase transition of the first class in gas of resonantly activated Rydberg atoms

S. Ya. Bronin^a, B. B. Zelener^ab, B. V. Zelener^a, A. B. Klyarfeld<sup>a

a</sup> Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow
^b National Research University "Moscow Power Engineering Institute"

Abstract: The equation of the state of the gas model of resonantly activated Rydberg atoms was calculated in the work with the help of the Monte Carlo method in the NVT ensemble. Variants of systems with arbitrarily and equally oriented dipole moments are considered. In both cases, critical parameters of the phase transition as well as binodal are determined. Critical temperatures almost coincide in both variants. However, the critical density for equally oriented dipoles is 20 times lower. It is shown that a specific feature of the phase transition in dipole systems is the absence of spatial separation in the region of the coexistence of dense and rarefied phases, which is due to the topological features of clusters of the dense phase. The parameters for the experimental observation of the self-organization of ultra-cold Rydberg atoms on the existing experimental stands are determined. The discovered self-organization of atoms in resonantly activated gas in the form of chains opens up new possibilities for creating quantum computers on Rydberg atoms.

Keywords: dipole interaction, Rydberg atoms, phase transitions.

Received: 19.11.2018

DOI: 10.23670/IRJ.2018.77.11.002

 English version: DOI: 10.23670/IRJ.2018.77.11.002