Dynamical signature of vortex mass in Fermi superfluids

TL;DR

This paper demonstrates that in Fermi superfluids, vortices possess a finite inertial mass due to the normal component in their cores, affecting their dynamics and observable through transverse oscillations.

Contribution

It reveals the inertial mass of vortices in Fermi superfluids and confirms this through large-scale simulations across various conditions.

Findings

Vortices in Fermi superfluids have finite inertial mass.

Transverse oscillations of vortices match predictions of a simple model with mass.

The normal component in the vortex core causes the observed inertia.

Abstract

Quantum vortices are commonly described as funnel-like objects around which the superfluid swirls, and their motion is typically modeled in terms of massless particles. Here we show that in Fermi superfluids the normal component confined in the vortex core provides the vortex with a finite inertial mass. This inertia imparts an unambiguous signature to the dynamic behavior of vortices, specifically manifesting as small-amplitude transverse oscillations which remarkably follow the prediction of a simple point-like model supplemented by an effective mass. We demonstrate this phenomenon through large-scale time-dependent simulations of Fermi superfluids across a wide range of interaction parameters, at both zero and finite temperatures, and for various initial conditions. Our findings pave the way for the exploration of inertial effects in superfluid vortex dynamics.