Groundstate properties of the BCS-Bose Einstein crossover in a $d_{x^{2}-y^{2}}$ wave superconductor

B. C. den Hertog

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arXiv · cond-mat/9808051

Groundstate properties of the BCS-Bose Einstein crossover in a $d_{x^{2}-y^{2}}$ wave superconductor

B. C. den Hertog

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Abstract

We examine the groundstate properties of the crossover between BCS superconductivity and Bose Einstein condensation within a model which exhibits $d_{x^{2} - y^{2}}$ pairing symmetry. We compare results for zero temperature with known features of s-wave systems and show that bosonic degrees of freedom are likely to emerge only in the dilute limit. We relate the change in properties of the groundstate as a function of density to the effect of the exclusion principle and show that the one particle distribution function undergoes a significant change when bosonic behavior appears.

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B. C. den Hertog. 1999-03-29. Groundstate properties of the BCS-Bose Einstein crossover in a $d_{x^{2}-y^{2}}$ wave superconductor. https://arxiv.org/abs/cond-mat/9808051

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