Engineering non-Gaussian entangled states with vortices by photon subtraction
Girish Saran Agarwal · New Journal of Physics · 2011
We show how a quantum mechanical vortex state of a two-mode system can be generated from a squeezed vacuum by subtracting a photon. The vortex state has nonclassical properties; for example, its Wigner function can be negative, in contrast to the Wigner function of the two-mode squeezed vacuum. We show, by calculating the logarithmic negativity parameter, that the vortex state has stronger entanglement than the two-mode squeezed vacuum.