A Robust Micro-Integrated Rubidium Saturated Absorption Spectroscopy Laser Reference

We have developed a novel millimetre-sized monolithic fibre-coupled rubidium saturated absorption spectroscopy laser reference suitable for quantum sensing applications. It is based on our novel MEMs vapour cell technology and bonding of optical elements to create a monolithic spectroscopy module. Our unit reproduces the signal visibility of a 70 mm long cell and is compatible with standard packaging techniques. The unit has no free-space elements that would otherwise be subject to vibration. Our reference uniquely combines the qualities of robustness, miniaturisation and signal strength providing an optimal solution for mobile quantum sensing platforms including space and aerospace.