1204.3761 (Ranjith Nair)

Fundamental limits on the accuracy of optical phase estimation from
rate-distortion theory    [PDF]

Ranjith Nair

Lower bounds are derived on the average mean-squared error of optical phase estimation in a Bayesian framework using classical rate-distortion theory in conjunction with the classical capacity of the lossy and lossless optical channel under phase modulation. With no optical loss, the bound displays Heisenberg-limit scaling of the mean-squared error \delta\Phi^2 \sim 1/N_S^2 where N_S is the average number of photons in the probe state. In the presence of nonzero loss, a lower bound with standard-quantum-limit (SQL) asymptotic scaling is derived. The bounds themselves are non-asymptotic and valid for any prior probability distribution of the phase.

View original: http://arxiv.org/abs/1204.3761