Non-Hermitian BCS-BEC crossover of Dirac fermions

Takuya Kanazawa

doi:10.1007/jhep03(2021)121

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arXiv · 2009.13363

Non-Hermitian BCS-BEC crossover of Dirac fermions

Takuya Kanazawa

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Abstract

We investigate chiral symmetry breaking in a model of Dirac fermions with a complexified coupling constant whose imaginary part represents dissipation. We introduce a chiral chemical potential and observe that for real coupling a relativistic BCS-BEC crossover is realized. We solve the model in the mean-field approximation and construct the phase diagram as a function of the complex coupling. It is found that the dynamical mass increases under dissipation, although the chiral symmetry gets restored if dissipation exceeds a threshold.

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Takuya Kanazawa. 2020-09-28. Non-Hermitian BCS-BEC crossover of Dirac fermions. https://doi.org/10.1007/jhep03(2021)121

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