Abstract

The best resolution of the standard interferometer pumped with a light in a coherent state, scales as ⟨n⟩^−½, where ⟨n⟩ is the mean photon number in a mode. Using more complicated quantum states of light it is possible to overcome this limit and reach so-called Heisenberg limit with phase resolution scales as ⟨n⟩⁻¹. In order to reach this limit non-classical states, or more complicated non-linear beam splitters instead of the passive 50/50 splitters must be used. That’s why resolution better than ⟨n⟩^−½ is hard to reach in a real interferometer.

© 1998 IEEE