Non-classical properties of states generated by the superposition of excited coherent states

The superposition of two excited coherent states of identical intensity but different phases yields a state that can exhibit varied non-classical char acteristics. Under suitable conditions, as the phase difference changes, th e mean photon number of the superposition state exhibits oscillations in a manner similar to the phenomenon of collapses and revivals of Rabi oscillat ions; phase squeezing and sub-Poissonian character of the field in such sta tes are stronger than those of single excited coherent state.