Quantum metrology with entangled coherent states

Jaewoo Joo, William J. Munro, Timothy P. Spiller

Published 2011-01-26, updated 2011-11-29Version 3

We present an improved phase estimation scheme employing entangled coherent states and demon- strate that the states give the smallest variance in the phase parameter in comparison to NOON, BAT and "optimal" states under perfect and lossy conditions. As these advantages emerge for very modest particle numbers, the optical version of entangled coherent state metrology is achievable with current technology.