High-momentum distribution with a subleading k−3 tail in odd-wave interacting one-dimensional Fermi gases

Abstract

We study odd-wave interacting identical fermions in one dimension with finite effective range. We show that to fully describe the high-momentum distribution $\ensuremath{\rho}(k)$ up to ${k}^{\ensuremath{-}4}$, one needs four parameters characterizing the properties when two particles contact each other. Two parameters are related to the variation of energy with respect to the odd-wave scattering length and the effective range, respectively, determining the ${k}^{\ensuremath{-}2}$ tail and part of the ${k}^{\ensuremath{-}4}$ tail in $\ensuremath{\rho}(k)$. The other two parameters are related to the center-of-mass motion of the system, respectively determining the ${k}^{\ensuremath{-}3}$ tail and the other part of the ${k}^{\ensuremath{-}4}$ tail. We point out that the unusual ${k}^{\ensuremath{-}3}$ tail, which has not been discovered before in atomic systems, is an intrinsic component to complete the general form of $\ensuremath{\rho}(k)$ and also is realistically detectable under certain experimental conditions. Various other universal relations are also derived in terms of those contact parameters, and finally the results are confirmed through the exact solution of a two-body problem.