Functionalized mm-scale vapor cells for alkali-metal spectroscopy and magnetometry

The entry contains numerical data displayed in Figures 3 and 4 of the manuscript titled above, see arXiv preprint: https://arxiv.org/abs/2405.10715

Authors: Harini Raghavan, Michael C. D. Tayler, Kostas Mouloudakis, Rachel Rae, Sami Lähteenmäki, Rasmus Zetter, Petteri Laine, Jacques Haesler, Laurent Balet, Thomas Overstolz, Sylvain Karlen, Morgan W. Mitchell

Abstract: We describe micro-fabricated rubidium vapor cells with integrated temperature-control functionality and demonstrate their suitability for use in miniaturized ultra-sensitive magnetometers. These functionalized vapor cells (FVCs) embody a dual-chamber design in low-conductivity silicon with anti-permeation coatings and micro-structured thin-film platinum surface traces as resistive heaters and temperature sensors. Thermal tests show our ability to control alkali metal distribution within the FVCs, ensuring a clean sensing chamber for optical measurements. Optical absorption spectroscopy is used to correlate the temperature readings with vapor density and to measure buffer gas pressure, of interest for optimizing sensitivity. Finally, we demonstrate zero-field resonance magnetometry with 18 fT/√Hz sensitivity in the 10 Hz to 100 Hz band, limited by laser noise and magnetic shield noise, which indicates that the functionalization does not introduce significant magnetic noise.