Pairing in spin polarized two-species fermionic mixtures with mass asymmetry

TL;DR

This paper investigates the pairing mechanisms in spin-polarized two-species fermionic mixtures with mass asymmetry, analyzing the BCS-BEC crossover and stability of breached pairing solutions at low temperatures.

Contribution

It introduces a variational approach to study pairing in asymmetric fermionic systems and explores the stability of breached pairing in the BEC regime.

Findings

Breached pairing with a single Fermi surface is stable in the BEC regime.

Temperature effects on fermion pairing are analyzed at low temperatures.

The study provides insights into pairing mechanisms with mass asymmetry in fermionic mixtures.

Abstract

We discuss on the pairing mechanism of fermions with mismatch in their fermi momenta due to a mass asymmetry. Using a variational ansatz for the ground state we also discuss the BCS -BEC crossover of this system. It is shown that the breached pairing solution with a single fermi surface is stable in the BEC regime. We also include the temperatures effect on the fermion pairing within an approximation that is valid for temperatures much below the critical temperature.