Higher angular momentum pairing from transverse gauge interactions

Article

关键词: VANQUISHED FERMI-LIQUID;    FILLED LANDAU-LEVEL;    T-J MODEL;    SUPERCONDUCTIVITY;    ENERGY;    DENSITY;    SYSTEMS;    MATTER;    FIELD;   

DOI  :  10.1103/PhysRevB.88.045127

来源: SCIE

【 摘 要 】

In this paper, we study the superconductivity of nonrelativistic fermions at finite-density coupled to a transverse U(1) gauge field, with the effective interaction including the Landau-damping. This model, first studied by Holstein, Norton, and Pincus [Phys. Rev. B 8, 2649 (1973)] has been known as an example of a non-Fermi liquid, i.e., a metallic state in which the decay rate of a quasiparticle is large compared to the characteristic quasiparticle energy; other examples of the non-Fermi liquid includes the two dimensional (2d) electron gas in a magnetic field at nu = 1/2 and the normal state of optimally doped cuprate superconductors. Our study thus addresses the question of whether or not non-Fermi liquids, like Fermi liquids, are unstable towards the formation of superconductivity. The results are (i) the non-Fermi liquid is stable against superconductivity below a critical gauge coupling, (ii) above this critical coupling, the ground state is an unconventional superconductor with angular momentum l >= 2. Our results are obtained from a solution of the Dyson-Nambu equation. Note that in this problem there is a quantum critical point between a non-Fermi liquid state and the superconducting state, as the critical coupling is nonzero. This is in contrast to a weakly coupled metal, which exhibits superconductivity for infinitesimally weak interaction regardless of its sign.

【 授权许可】

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