Eur. Phys. J. D 37, 427-433 (2006)
https://doi.org/10.1140/epjd/e2005-00318-y

Renormalization group approach to the spin-1 Bose gas

Research Group for Statistical Physics of the Hungarian Academy of Sciences, Pázmány Péter Sétány 1/A, Budapest, 1117, Hungary

Corresponding author: ^a szirmai@complex.elte.hu

Received: 24 June 2005
Revised: 25 August 2005
Published online: 29 November 2005

Abstract

A field theoretical renormalization group approach at two loop level is applied to the homogeneous spin-1 Bose gas in order to investigate the order of the phase transition. The beta function of the system with d=4-ϵ dimensions is determined up to the third power of the coupling constants and the system's free energy on the border of the classical stability is given in next to leading order. It is found that the phase transition of the interacting spin-1 Bose gases with weak spin-dependent coupling constant values is of first order.