Room temperature xenon magnetometer could rival the best quantum sensors

[Lily98]

A team at the University of Alberta has proposed a new type of room temperature magnetometer that could outperform today's best sensors. Quantum Zeitgeist reports on the analysis by James Maldaner and Gil Porat. Their design reads out xenon-129 atoms directly with ultraviolet light

Most sensitive atomic magnetometers use alkali vapour, such as rubidium or caesium. The best of these already rival SQUIDs, which need cryogenic cooling. Noble gases like xenon have very long lived spin states, which makes them attractive for sensing, but reading them out has been difficult

The researchers predict a sensitivity of 24 attotesla per root hertz after about ten minutes, using a 10 watt ultraviolet laser. That compares with about 160 for today's best atomic magnetometers. Xenon spin relaxation times above 10 milliseconds are cited, and polarisation can last for hours at room temperature

The proposed light source is a powerful ytterbium fibre frequency comb, quadrupled in frequency to 256 nanometres to drive two photon excitation of xenon. Laser intensity noise is the main limit. With a weaker 1 watt laser and more noise, the predicted sensitivity drops to 148, still competitive but less dramatic

These are theoretical predictions rather than a lab demonstration, and the authors say more laser power is needed than has been used so far. Still, sensors this sensitive at room temperature would be valuable for brain imaging, geology and fundamental physics. It will be exciting to see whether experiments can match the predictions

Could room temperature sensors replace cryogenic ones? And how hard will building such a powerful UV laser be?

Room-temperature Quantum Sensor Skips The Need For Cryogenic Coolingquantumzeitgeist.com