Vapor cells for quantum sensors
Featuring Thomas Overstolz | Focus Area Manager of the MEMS & Packaging activity, Centre Suisse d’Electronique et de Microtechnique

Modern quantum sensors based on sensing of hot vapors are of growing interest in the scientific community. At the core of these applications is the vapor cell, a small container filled with metallic alkali atoms (e.g. rubidium or cesium). In recent years, the fabrication of these cells has experienced enormous progress, starting from glass-blown cells, over single MEMS fabricated cells using custom-designed equipment, to an industrial approach using standard MEMS fabrication techniques allowing the fabrication of hundreds of vapor cells at once on a single wafer (150mm diameter in our case). Recently, the European quantum flagship project “macQsimal” was successfully terminated. This project, coordinated by CSEM, brought together 14 partners from academia, research and technology organizations, and industries from seven European countries. The project was built around the atomic vapor cell and its use in 5 quantum sensing applications: atomic clocks, optically pumped magnetometers, nuclear magnetic resonance gyroscopes, GHz- and THz-imaging, and gas sensors based on sensing of Rydberg states. An overview of the project achievements will be given in this talk, highlighting the different quantum sensor prototypes and demonstrators developed during the last four years.

Bio: Thomas Overstolz received his Ph.D. in science from the University of Neuchâtel (Switzerland) in 2007, based on his work on MEMS hybrid platforms for tuning of optical components. In 2005 he joined Centre Suisse d’Electronique et de Microtechnique (CSEM), where he works as senior R&D engineer and as project manager, responsible for MEMS technology integration in various projects. In 2022 he was appointed Focus Area Manager of the MEMS & Packaging activity. He is author and co-author of more than 50 scientific publications and eight patents.