One-loop omega-potential of charged massive particles in a constant homogeneous magnetic field at high temperatures

摘要

The explicit expressions for the high-temperature expansions of the one-loopcorrections to the omega-potential coming from charged scalar and Diracparticles and, separately, from antiparticles in a constant homogeneousmagnetic field are derived. The explicit expressions for the non-perturbativecorrections to the effective action at finite temperature and density areobtained. Thermodynamic properties of a gas of charged scalars in a constanthomogeneous magnetic field are analyzed in the one-loop approximation. It turnsout that, in this approximation, the system suffers a first-order phasetransition from the diamagnetic to the superconducting state at sufficientlyhigh densities. The improvement of the one-loop result by summing the ringdiagrams is investigated. This improvement leads to a drastic change inthermodynamic properties of the system. The gas of charged scalars passes tothe ferromagnetic state in place of the superconducting one at high densitiesand sufficiently low temperatures, in the high temperature regime.