Current parameter estimation techniques rely on photodetectors which have a low efficiency and thus are based on gathering averaged statistics. Recently it was claimed that perfect photodetction will change the nature of sensing algorithms and will increase the sensing efficiency beyond the immediate effect of a higher collection efficiency. In this paper we bring up the observation that perfect photodetection implies Heisenberg scaling $\left(\frac{1}{T}\right)$ for parameter estimations. We analyze a specific example in detail.

• Received 1 October 2015

DOI:https://doi.org/10.1103/PhysRevA.93.032133