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Enhanced Fermion Pairing and Superfluidity by an Imaginary Magnetic Field.

ABSTRACT: We show that an imaginary magnetic field (IMF), which can be generated in non-Hermitian systems with spin-dependent dissipations, can greatly enhance the s-wave pairing and superfluidity of spin-1/2 fermions, in distinct contrast to the effect of a real magnetic field. The enhancement can be attributed to the increased coupling constant in low-energy space and the reduced spin gap in forming singlet pairs. We have demonstrated this effect in a number of different fermion systems with and without spin-orbit coupling, using both the two-body exact solution and many-body mean-field theory. Our results suggest an alternative route toward strong fermion superfluid with high superfluid transition temperature.

SUBMITTER: Zhou L

PROVIDER: S-EPMC6463221 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Enhanced Fermion Pairing and Superfluidity by an Imaginary Magnetic Field.

Zhou Lihong L Cui Xiaoling X

iScience 20190403

We show that an imaginary magnetic field (IMF), which can be generated in non-Hermitian systems with spin-dependent dissipations, can greatly enhance the s-wave pairing and superfluidity of spin-1/2 fermions, in distinct contrast to the effect of a real magnetic field. The enhancement can be attributed to the increased coupling constant in low-energy space and the reduced spin gap in forming singlet pairs. We have demonstrated this effect in a number of different fermion systems with and without ...[more]

PMID: 30986690

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