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Condensation in ideal Fermi gases

Dragoş-Victor Anghel
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Abstract

I investigate the possibility of condensation in ideal Fermi systems of general single particle density of states. For this I calculate the probability $w_{N_0}$ of having exactly $N_0$ particles in the condensate and analyze its maxima. The existence of such maxima at macroscopic values of $N_0$ indicates a condensate. An interesting situation occurs for example in 1D systems, where $w_{N_0}$ may have two maxima. One is at $N_0=0$ and another one may exist at finite $N_0$ (for temperatures bellow a certain condensation temperature). This suggests the existence of a first order phase transition. % The calculation of $w_{N_0}$ allows for the exploration of ensemble equivalence of Fermi systems from a new perspective.

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Dragoş-Victor Anghel. 2003-10-22. Condensation in ideal Fermi gases. https://doi.org/10.1088/0305-4470%2F36%2F46%2Fl01

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