Micro-machined deep silicon atomic vapor cells

TL;DR

This paper presents a cost-effective water jet process to create deep silicon atomic vapor cells up to 6mm, enabling improved signal strength and complex geometries for atomic sensing applications.

Contribution

It introduces a novel fabrication method for deep silicon vapor cells with a two-chamber design, overcoming previous size limitations and enhancing vapor signal quality.

Findings

Successful fabrication of 6mm deep vapor cells

Demonstration of a two-chamber geometry with a meandering channel

Enhanced signal compared to standard 2mm cells

Abstract

Using a simple and cost-effective water jet process, silicon etch depth limitations are overcome to realize a $6\,$mm deep atomic vapor cell. While the minimum silicon feature size was limited to a $1.5\,$mm width in these first generation vapor cells, we successfully demonstrate a two-chamber geometry by including a $\sim$25~mm meandering channel between the alkali pill chamber and main interrogation chamber. We evaluate the impact of the channel conductance on the introduction of alkali vapor density during the pill activation process, and mitigate glass damage and pill contamination near the main chamber. Finally, we highlight the improved signal achievable in the $6\,$mm silicon cell compared to standard $2\,$mm path length silicon vapor cells.