Quantum phase measurements with infinite peak-likelihood and zero phase information
Z. Hradil, J.H. Shapiro · Quantum Optics Journal of the European Optical Society Part B · 1992
Maximum likelihood estimation of an unknown c-number phaseshift is considered, along the lines established by Shapiro, Shepard and Wong, Phys. Rev. Lett., vol.62, p.2377, 1989. An input state is exhibited whose reciprocal peak likelihood vanishes, delta phi to 0, while its phase-measurement probability density converges, in distribution, to uniform, p( phi mod Phi ) to d 1/2 pi .