ARRS project J2-8191 – High-resolution optical magnetometry with cold cesium atoms
Project leader: Dr. Peter Jeglič
Vapor cells with alkali atoms are already used in precise hot-vapor atomic magnetometers and are in many applications already replacing SQUID magnetometers (e.g., as NQR, NMR, biomagnetic signal detectors, in physics and metrology research laboratories). Compared to SQUID devices they do not need complicated cryogenic cooling, they exhibit better sensitivity, are compact, much cheaper to operate and do not need calibration. Next step in the development of an ultimate magnetic sensor is to replace hot atoms with cold atoms. Similar evolution from using hot to using cold atoms is already under way in timekeeping experiments, where clocks with cold atoms surpass the standard cesium clock stability by several orders of magnitude.
The main advantages of cold-atom over hot-vapor magnetometers are better spatial resolution, longer coherence times and a negligible Doppler broadening, making them even more sensitive and precise. Because of the small volume of cold atoms cloud (a few tenths of a mm in diameter) these sensors could also be used for spatially resolved magnetic field measurements and for measurements of magnetic fields gradients. The magneto-optical methods of cold-atom experiments provide a precise control over the position, number, density, temperature and of quantum states of trapped atoms. It is also possible to fine tune the interactions between cesium atoms via Feshbach resonances. These parameters make cold atoms ideal testing platform for quantum technologies. In this project we propose the development of a novel cesium cold-atoms magnetometer. Not only are we planning to prove basic concepts but are striving toward a working magnetic sensor, capable of detecting nuclear magnetic resonance (NQR) signal from a real sample.