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Classification of the pairing transition in finite fermionic systems

A. Belic·D. J. Dean·M. Hjorth-Jensen
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Abstract

In this work we employ a simple pairing interaction model in order to study and classify an eventual pairing phase transition in finite fermionic systems. We show that systems with as few as 10-16 fermions can exhibit clear features reminiscent of a phase transition. To classify the nature of the transition we apply two different numerical methods, one based on standard thermodymanics, and another based on a recently proposed scheme by Borrmann et al. [Phys. Rev. Lett. 84, 3511 (2000)]. The transition is shown to be of second order, in agreement with results for infinite fermionic systems.

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A. Belic, D. J. Dean, M. Hjorth-Jensen. 2001-04-09. Classification of the pairing transition in finite fermionic systems. https://arxiv.org/abs/cond-mat/0104138

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