Fermion Cooper pairing with unequal masses: Standard field theory approach
Lianyi He, Meng Jin, Pengfei Zhuang
DOI 10.1103/PhysRevB.74.024516 · Physical Review B
Active bibliographic source — not scientific approval
Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.
Abstract
Fermion Cooper pairing with unequal masses is investigated in a standard field theory approach. We derived the superfluid density and Meissner mass squared of the U(1) gauge field in a general two-species model and found that the often used proportional relation between the two quantities is broken when the fermion masses are unequal. In the weak-coupling region, the superfluid density is always negative but the Meissner mass squared becomes mostly positive when the mass ratio between the pairing fermions is large enough. We established a proper momentum configuration of the LOFF pairing with unequal masses and showed that the LOFF state is energetically favored due to the negative superfluid density. The single-plane-wave LOFF state is physically equivalent to an anisotropic state with a spontaneously generated superflow. The extension to a finite-range interaction is briefly discussed.
Similar papers
Fermion Cooper Pairing with Unequal Masses: Standard Field Theory Approach
similarity 0.91Lianyi He et al. · 2006 · arXiv:cond-mat/0604137
Source status unknown — claims are unverified
Superfluid density reduction and spin-imbalanced pairing in a fermionic superfluid due to dynamical boson exchange
similarity 0.88Ziyue Wang & Lianyi He · 2018 · arXiv:1805.04858
Source status unknown — claims are unverified