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Exact ground state number fluctuations of trapped ideal and interacting fermions

Muoi N. Tran
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Abstract

We consider a small and fixed number of fermions in an isolated one-dimensional trap (microcanonical ensemble). The ground state of the system is defined at T=0, with the lowest single-particle levels occupied. The number of particles in this ground state fluctuates as a function of excitation energy. By breaking up the energy spectrum into particle and hole sectors, and mapping the problem onto the classic number partitioning theory, we formulate a new method to calculate the exact particle number fluctuation more efficiently than the direct combinatorics method. The exact ground state number fluctuation for particles interacting via an inverse-square pair-wise interaction is also calculated.

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Muoi N. Tran. 2002-08-16. Exact ground state number fluctuations of trapped ideal and interacting fermions. https://doi.org/10.1088/0305-4470/36/4/308

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