Haine, SimonLecamwasam, RuvindhaHope, JosephSelim M ShahriarJacob Scheuer2020-04-142020-04-14February 297815106251050277-786Xhttp://hdl.handle.net/1885/202930We 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. We 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. We 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.This work was supported by Australian Research Council Discovery Project DP190101709.application/pdfen-AU© 2019 SPIE201910.1117/12.25118352020-01-27