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Temperature-induced pair correlations in clusters and nuclei

S. Frauendorf·N. K. Kuzmenko·V. M. Mikhajlov·J. Sheikh
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Abstract

The pair correlations in mesoscopic systems such as $nm$-size superconducting clusters and nuclei are studied at finite temperature for the canonical ensemble of fermions in model spaces with a fixed particle number: i) a degenerate spherical shell (strong coupling limit), ii) an equidistantly spaced deformed shell (weak coupling limit). It is shown that after the destruction of the pair correlations at T=0 by a strong magnetic field or rapid rotation, heating can bring them back. This phenomenon is a consequence of the fixed number of fermions in the canonical ensemble.

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S. Frauendorf, N. K. Kuzmenko, V. M. Mikhajlov, J. Sheikh. 2003-01-16. Temperature-induced pair correlations in clusters and nuclei. https://doi.org/10.1103/physrevb.68.024518

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