Optimization of Nuclear Polarization in an Alkali-Noble Gas Comagnetometer

Self-compensated comagnetometers, employing overlapping samples of spin-polarized alkali and noble gases (for example K-${}^{3}\mathrm{He}$) are promising sensors for exotic beyond-the-standard-model fields high-precision metrology such as rotation sensing. When the comagnetometer operates in so-called self-compensated regime, effective field, originating from contact interactions between valence electrons noble-gas nuclei, is compensated with an applied magnetic field. begins operation a given spin-exchange optical pumping establishes equilibrium electron-spin polarization nuclear-spin polarization. Subsequently, when field tuned to compensation point, spin brought out conditions. This causes practical issue long measurement times. We report on method closed-loop control allows optimization operating parameters, especially gradients, spite inherently slow (hours days) dynamics system. With optimization, higher stable nuclear polarization, longer relaxation times, stronger electron-nuclear coupling achieved which useful nuclear-spin-based quantum memory, amplifiers, gyroscopes. The optimized sensor demonstrates sensitivity comparable best previous but four times lower density. paves way applications both fundamental science.