We propose and analyze a driven-dissipative quantum sensor that is continuously monitored close to a dissipative critical point. The sensor relies on the critical open Rabi model with the spin and phonon degrees of freedom of a single trapped ion to achieve criticality-enhanced sensitivity. Effective continuous monitoring of the sensor is realized via a co-trapped ancilla ion that switches between dark and bright internal states conditioned on a ‘jump’ of the phonon population which, remarkably, achieves nearly perfect phonon counting despite a low photon collection efficiency. By exploiting both dissipative criticality and efficient continuous readout, the sensor device achieves highly precise sensing of oscillating electric field gradients at a criticality-enhanced precision scaling beyond the standard quantum limit, which we demonstrate is robust to the experimental imperfections in real-world applications.

我们提出并分析了一种驱动耗散量子传感器，该传感器在接近耗散临界点时连续监测。该传感器依靠具有单个捕获离子的自旋和声子自由度的临界开放拉比模型来实现临界增强的灵敏度。传感器的有效连续监测是通过共捕获的辅助离子实现的，该辅助离子根据声子群的“跳跃”在暗和亮内部状态之间切换，值得注意的是，尽管光子收集效率较低，但仍实现了近乎完美的声子计数。通过利用耗散临界性和高效的连续读出，传感器设备以超出标准量子极限的临界增强精度缩放实现了振荡电场梯度的高精度感测，我们证明这对现实应用中的实验缺陷具有鲁棒性。