2018/06/30 by Simon A. Haine · 1 citation
Physics and Astronomy · #quant-ph #cond-mat.quant-gas
paper · pdf · doi:10.1103/physreva.98.030303
published as Phys. Rev. A 98, 030303 (2018)
arxiv created 2018/09/29 · arxiv updated 2018/10/31
I consider the role of detection noise in quantum-enhanced metrology in collective spin systems, and derive a fundamental bound for the maximum obtainable sensitivity for a given level of added detection noise. I then present an interaction-based readout utilising the commonly used one-axis twisting scheme that approaches this bound for states generated via several commonly considered methods of generating quantum enhancement, such as one-axis twisting, two-axis counter-twisting, twist-and-turn squeezing, quantum non-demolition measurements, and adiabatically scanning through a quantum phase transition. I demonstrate that this method performs significantly better than other recently proposed interaction-based readouts. These results may help provide improved sensitivity for quantum sensing devices in the presence of unavoidable detection noise.