Abstract
In this work, a Josephson relation is generalized to a multi-component fermion superfluid. Superfluid density is expressed through a two-particle Green function for pairing states. When the system has only one gapless collective excitation mode, the Josephson relation is simplified, which is given in terms of the superfluid order parameters and the trace of two-particle normal Green function. In addition, it is found that the matrix elements of two-particle Green function is directly related to the matrix elements of the pairing fluctuations of superfluid order parameters. Furthermore, in the presence of inversion symmetry, the superfluid density is given in terms of the pairing fluctuation matrix. The results of the superfluid density in Haldane model show that the generalized Josephson relation can be also applied to a multi-band fermion superfluid in lattice.
Highlights
It is found that the superfluid density is given in terms of two-particle Green functions
When the superfluid has only one gapless collective excitation, the Josephson relation can be simplified, which is given in terms of superfluid order parameters and trace of Green function
Within BCS mean field theory and Gaussian fluctuation approximation, the matrix elements of Green function can be given in terms of pairing fluctuation matrix elements
Summary
When the system has only one gapless collective excitation mode, the Josephson relation is simplified, which is given in terms of the superfluid order parameters and the trace of two-particle normal Green function. It is found that the matrix elements of two-particle Green function is directly related to the matrix elements of the pairing fluctuations of superfluid order parameters. Is superfluid order parameter (pairing gap in superconductor) and GII (q, ω) is two-particle Green function for pairing states in conventional two-component fermion superfluid.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
