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arXiv · 1801.07377

First-order phase transition by a spin-flip potential in BCS superconductivity

Octavio D. Rodriguez Salmon·Igor Tavares Padilha·Francisco Dinóla Neto
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Abstract

A spin-flip potential $V$ is introduced in a BCS Hamiltonian in order to study a possible thermodynamic effect that might be caused by the addition of a magnetic impurity in a superconductor. We found that the competition between the pairing and the spin-flip effect, caused by the interaction between the itinerant electrons and the spin of the impurity, gives rise to a first-order phase transition for certain values of $V$. The phase diagram shows a tricritical point in a frontier line which is topologically similar to those found in the phase diagrams of some Ising-like models.

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Octavio D. Rodriguez Salmon, Igor Tavares Padilha, Francisco Dinóla Neto. 2018-01-23. First-order phase transition by a spin-flip potential in BCS superconductivity. https://doi.org/10.1016/j.physc.2019.05.007

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