Optimal thickness of rectangular superconducting microtraps for cold atomic gases

TL;DR

This paper investigates the design of superconducting microtraps with rectangular geometries for cold atomic gases, identifying optimal thicknesses and exploiting edge effects to enhance trap proximity.

Contribution

It introduces a method to determine the optimal thickness of rectangular superconducting microtraps and demonstrates how edge enhancement improves trap closeness to the superconductor surface.

Findings

Existence of an optimal thickness for microtraps

Edge enhancement significantly improves trap proximity

Conformal mapping provides useful approximations

Abstract

We study superconducting microtraps with rectangular shapes for cold atomic gases. We present a general argument why microtraps open, if brought close to the surface of the superconductor. We show that for a given width of the strips there exists an optimal thickness under which the closest distance of the microtrap from the superconductor can be achieved. The distance can be significantly improved, if the edge enhancement of the supercurrent near edges and corners is exploited. We compare numerical calculations with results from conformal mapping and show that conformal mapping can often give useful approximate results.