Quantum metrology with partially concurrent twisting and sensing

We propose a quantum-enhanced metrology protocol known as partially concurrent twisting and sensing (PCTS) to effectively utilize time for high-precision sensing. In contrast to the traditional approach of separated twisting and sensing (STS), we concurrently execute twisting and sensing at the outset. Here, we explore one-axis twisting (OAT) over a short evolution period to induce spin squeezing, which has been used in several quantum-enhanced metrology. In particular for tiny estimated parameter, we analytically give the measurement precision of PCTS and demonstrate its metrological advantages compared with STS. Especially for modest particle number and OAT interaction strength, PCTS makes better use of entanglement generation time and achieves a larger metrological gain within the same total time. We estimate that our PCTS may offer up to 2 dB of metrological advantage over STS in realistic experiments with Bose condensed atoms or trapped ions. Although the measurement precision of PCTS may diminish with increasing estimated parameters, we can employ two hybrid classical-PCTS compensation techniques to facilitate high-precision measurements across a wide dynamic range. Furthermore, our approach eliminates the need to switch the estimated field, thereby reducing experimental demands and offering extensive application potential in atomic clocks and magnetometers.