Bose-Einstein condensation of a nonideal gas

Vladimir Sergeevich Yarunin

J. R. Anglin, Wolfgang Ketterle

Alexander I. Akhiezer, S. V. Peletminskiǐ, Yu. V. Slyusarenko

This paper investigates Bose-Einstein condensation of an ideal gas of finite-spin bosons in an external magnetic field. We generalize Bogolyubov’s theory of a weakly nonideal Bose gas to the case where the gas of finite-spin bosons is located in an external magnetic field. We find the corresponding quasiparticle spectrum and formulate the superfluidity criterion for the boson gas. The magnetization of the weakly nonideal Bose gas is also determined. Finally, we specify a method of studying kinetic processes that take place in a weakly nonideal Bose gas.

Randall G. Hulet

Vladimir Sergeevich Yarunin

The theory of a nonideal gas developed by N. N. Bogoliubov is applied for a semiclassical description of nonlinear dynamics of Bose condensate density. Analytical calculations lead to temperature dependence of heat capacity Cv typical of superfluid He4 at temperatures below and above the superconducting transition temperature Tc except for the interval 1.6 K<T<2.2 K.

Società italiana di fisica, Carl Wieman, S. Stringari