Detection of nonclassical states using a Kerr medium
Mark S. Hillery · Physical Review A · 1991
It is possible to determine whether the input state to a Kerr medium is nonclassical by measuring the total noise of the output state. For a classical input state the total noise at the output has a minimum value that depends on the photon number and the interaction time. If the total noise is found to be less than this value, then it can be concluded that the input state was nonclassical. A certain class of generalized coherent states can be detected in this way.