Sound Velocity and Meissner Effect in Light-heavy Fermion Pairing Systems

TL;DR

This paper explores collective excitations in light-heavy fermion pairing systems, revealing that sound velocity and Meissner mass depend on mass ratios similarly to transition temperature and energy gap.

Contribution

It introduces a theoretical analysis linking collective excitation properties to mass ratios in light-heavy fermion systems, a novel insight in fermionic superfluidity and superconductivity.

Findings

Sound velocity and Meissner mass depend on mass ratios.

Dependence matches the ratio of transition temperature to zero-temperature gap.

Same mass ratio dependence observed in superfluid and superconductor properties.

Abstract

In the frame of a four fermion interaction theory, we investigated the collective excitation in light-heavy fermion pairing systems. When the two species of fermions posses different masses and chemical potentials but keep the same Fermi surface, we found that the sound velocity in superfluids and the Meissner mass or inverse penetration depth in superconductors have the same mass ratio dependence as the ratio of the transition temperature to the zero temperature gap.