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The Partition Function of a Spinor Gas

L. F. Lemmens·F. Brosens·J. T. Devreese
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Abstract

For a spinor gas, i.e., a mixture of identical particles with several internal degrees of freedom, we derive the partition function in terms of the Feynman-Kac functionals of polarized components. As an example we study a spin-1 Bose gas with the spins subjected to an external magnetic field and confined by a parabolic potential. From the analysis of the free energy for a finite number of particles, we find that the specific heat of this ideal spinor gas as a function of temperature has two maxima: one is related to a Schottky anomaly, due to the lifting of the spin degeneracy by the external field, the other maximum is the signature of Bose-Einstein condensation.

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BibTeXRIS

L. F. Lemmens, F. Brosens, J. T. Devreese. 2000-01-20. The Partition Function of a Spinor Gas. https://doi.org/10.1103/physreve.61.3358

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