Higher (2nd)-order polarization-Wigner function for `even' entangled   bi-modal coherent states
  Higher (2nd)-order Wigner distribution function in quantum phase space for entangled bi-modal coherent states, a representative of higher (2nd)-order optical-polarization, is introduced by generalizing kernel (transiting) operator in Cahill-Glauber C(s)-correspondence rule. The nature is analyzed which reveals the occurrence of oscillating three peaks: 'two' for individual bi-modes and third for interference between modes. Also, the graphics of 2nd-order polarization-Wigner distribution function, incisively, demonstrates that it is of non-Gaussian nature attaining non-negative values in quantum phase space. 
Ravi S. Singh, Sunil P. Singh, Lallan Yadava and Gyaneshwar K. Gupta
quant-ph physics.optics