We describe and operate a spin-magnetometer based on the phase modulation of cavity magnon polaritons. In this scheme a rf magnetic field is detected through the sidebands it induces on a pump, and the experimental configuration allows for a negligible pump noise and a high-frequency readout. The demonstrator setup, based on a copper cavity coupled to an yttrium iron garnet sphere hybrid system, reached a sensitivity of 2.0 pT/√Hz at 220 MHz, evading the pump noise and matching the theoretical predictions. An optimized setup can attain a rf magnetic field sensitivity of about 8 fT/√Hz at room temperature. An orders of magnitude improvement is expected at lower temperatures, making this instrument one of the few magnetometers accessing the subfemtotesla limit.
Phase-modulated cavity magnon polaritons as a precise magnetic field probe
Crescini, N.;
2021-01-01
Abstract
We describe and operate a spin-magnetometer based on the phase modulation of cavity magnon polaritons. In this scheme a rf magnetic field is detected through the sidebands it induces on a pump, and the experimental configuration allows for a negligible pump noise and a high-frequency readout. The demonstrator setup, based on a copper cavity coupled to an yttrium iron garnet sphere hybrid system, reached a sensitivity of 2.0 pT/√Hz at 220 MHz, evading the pump noise and matching the theoretical predictions. An optimized setup can attain a rf magnetic field sensitivity of about 8 fT/√Hz at room temperature. An orders of magnitude improvement is expected at lower temperatures, making this instrument one of the few magnetometers accessing the subfemtotesla limit.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
