Non-classical states in extended phase space
A family of coherent states, localized in ordinary phase space that minimize the uncertainty principle is often considered as classical states. One may ask a question that to what extent a quantum state is non-classical [1, 2] in a sense that its properties differs from that of coherent states? To answer this question we define a parameter for a given quantum distribution function in extended phase space that legitimately reflects its degree of non-classicality. As an example, the non-classicality which may be interpreted as a signature of quantum interference, is demonstrated for the Schrodinger cat state using the corresponding quantum distribution function in different extended phase space representations [3, 4].
Joint work with Sadollah Nasiri (Zanjan University and Institute for Advanced Studies in Basic Sciences, Zanjan, Iran), Siamak Khademi and Samira Bahrami (Zanjan University, Iran)