Heating rate and spin flip lifetime due to near field noise in layered superconducting atom chips

TL;DR

This paper models how layered superconducting atom chips' near field noise affects atomic heating and spin flip lifetimes, comparing gold-coated and bare superconductors at different temperatures.

Contribution

It provides a theoretical comparison of near field noise effects on heating and spin flip lifetimes for layered superconducting atom chips at various temperatures.

Findings

Gold layers increase near field noise at 4.2 K, reducing lifetimes.

YBCO chips are less affected by gold layers at 77 K.

Superconducting chips show temperature-dependent noise characteristics.

Abstract

We theoretically investigate the heating rate and spin flip lifetimes due to near field noise for atoms trapped close to layered superconducting structures. In particular, we compare the case of a gold layer deposited above a superconductor with the case of a bare superconductor. We study a niobium-based and a YBCO-based chip. For both niobium and YBCO chips at a temperature of 4.2 K, we find that the deposition of the gold layer can have a significant impact on the heating rate and spin flip lifetime, as a result of the increase of the near field noise. At a chip temperature of 77 K, this effect is less pronounced for the YBCO chip.