A passive atomtronics filter for Fermi gases

TL;DR

This paper proposes a novel atomtronic filter device using a barbell-shaped potential to spatially separate components of a two-component Fermi gas, demonstrating robustness and advancing DPFT as a simulation tool.

Contribution

It introduces a new trap design for component separation in Fermi gases and establishes DPFT as a reliable framework for fermionic atomtronics simulations.

Findings

Successful separation of fermion species in the proposed trap

Robustness of the filter against experimental variations

First application of DPFT in fermionic atomtronics

Abstract

We design an atomtronic filter device that spatially separates the components of a two-component Fermi gas with repulsive contact interactions in a two-dimensional geometry. With the aid of density--potential functional theory (DPFT), which can accurately simulate Fermi gases in realistic settings, we propose and characterize a barbell-shaped trapping potential, where a bridge-shaped potential connects two ring-shaped potentials. In the strongly repulsive regime, each of the ring traps eventually stores one of the fermion species. Our simulations are a guide to designing component filters for initially mixed, weakly repulsive spin components. We demonstrate that the functioning of this barbell design is robust against variations in experimental settings, for example, across particle numbers, for small deformations of the trap geometry, or if interatomic interactions differ from the bare contact repulsion. Our investigation marks the first step in establishing DPFT as a comprehensive simulation framework for fermionic atomtronics.