Effect of vortices on the spin-flip lifetime of atoms in superconducting atom-chips

TL;DR

This paper theoretically investigates how vortices in a type-II superconductor affect the spin-flip lifetime of atoms in superconducting atom-chips, showing vortices significantly influence atom losses but still outperform normal metal setups.

Contribution

It provides a detailed theoretical analysis of vortex-induced magnetic noise and quantifies its impact on atom lifetime near superconducting surfaces, specifically for niobium films.

Findings

Vortices significantly increase atom losses near superconducting surfaces.

Atom losses are much lower than in room-temperature metal atom-chips.

Superconducting atom-chips outperform normal metal chips despite vortex effects.

Abstract

We study theoretically the lifetime of magnetically trapped atoms in the close vicinity of a type-II superconducting surface, in the context of superconducting atom-chips. We account for the magnetic noise created at the cloud position by the vortices present in the superconductor and give specific results for our experiment which uses a niobium film. Our main result is that atom losses are dominated by the presence of vortices. They remain however dramatically smaller than in equivalent room-temperature atom-chip setups using normal metals.