European Journal of Physics
Bose-Einstein condensation for general dispersion relations
Valdir C. Aguilera-Navarro, MANUEL DE LLANO, M. A. Solís
Abstract
Bose-Einstein condensation in an ideal (i.e. interactionless) boson gas can be studied analytically, at university-level statistical and solid state physics, in any positive dimensionality ( d >0) for identical bosons with any positive-exponent ( s >0) energy-momentum (i.e. dispersion) relation. Explicit formulae with arbitrary d / s are discussed for: the critical temperature (non-zero only if d / s >1); the condensate fraction; the internal energy; and the constant-volume specific heat (found to possess a jump discontinuity only if d / s >2). Classical results are recovered at sufficiently high temperatures. Applications to `ordinary' Bose-Einstein condensation, as well as to photons, phonons, ferro- and antiferromagnetic magnons, and (very specially) to Cooper pairs in superconductivity, are mentioned.