[19p-Z19-1~7] 10.4 Semiconductor spintronics, superconductor, multiferroics

▲ [19p-Z19-5] Quantum sensing with both high sensitivity and large range

〇Ernst David Herbschleb¹, Hiromitsu Kato², Toshiharu Makino², Satoshi Yamasaki^2,3, Norikazu Mizuochi¹ (1.Kyoto Univ., 2.AIST, 3.Kanazawa Univ.)

Keywords:Quantum sensing, Nitrogen-vacancy centre, Dynamic range

Ultra-high resolution and sensitivity are two cornerstones for quantum sensing. An example of a quantum sensor is the electron spin of a nitrogen-vacancy centre. For sensors, the ratio between the largest possible range and the sensitivity in this range, called the dynamic range, is rather important. The limitation of spin systems for sensing is the small range, given the rotational symmetry of the phase of the spin, which thus limits the dynamic range. Here, we demonstrate and explore a technique to increase the range for AC magnetic fields beyond the limit of the standard measurement, while the sensitivity is practically unaltered, both unique features of our algorithm, thus maximally improving the dynamic range. This paves the way to fully utilising entanglement-based quantum sensors.