A Theoretical Study of a Photon Set Polarization State

Shujing Li, Hongmei Yan, Yaya He +1 more

We propose a scheme to generate polarized hybrid entanglement in the form of $|H\ensuremath{\rangle}|\ensuremath{\alpha}\ensuremath{\rangle}+|V\ensuremath{\rangle}|\ensuremath{-}\ensuremath{\alpha}\ensuremath{\rangle}$ by interference between a superposition of coherent states and a polarization entangled photon pair. In the scheme two sets of interferences with perpendicular polarizations are designed to erase ``which path'' information. The joint output fields of the two sets of interferences are used to herald the generation of the polarized hybrid entanglement. The advantage of the protocol is its experimental feasibility since it not only realizes effective interference but also retains the polarization information in the output fields of interferences. We also analyze the effect of imperfect experimental conditions on the generated hybrid state, including inefficiency on-off single-photon detectors with dark counts and available approximate resource states. The theoretical analysis shows that the fidelity of the heralded hybrid state with small amplitude can be maintained at a high level under actual experimental conditions.

Vanik E. Mkrtchian, V. O. Chaltykyan

Zhixin Yao, Zhong Jian-Wei, Mao Bang-Ning +1 more

Interference of light has been reinvestigated theoretically by linear superposition of two different state-vector functions, of which each describes the photons from one of two different light sources in both polarization and intensity. By the use of microscopic parameters for a photon, namely probability amplitude and phase, it is again validated that interference of light occurs only between the same photons possessing a set of the selfsame eigenvalues.

Osama M. Raisuddin, Suvranu De

P. R. Hammond, M. A. Khakoo, J. William McConkey

Measurements are presented representing a complete set of electron-photon polarization correlation parameters for the excitation of n $^{1}P$ states of He at an incident energy of 80 eV and an electron scattering angle of 20\ifmmode^\circ\else\textdegree\fi{}. The data support the predictions of a recent theoretical paper that these parameters should exhibit little variation with n. However, disagreement in absolute values between experiment and theory indicates the need for additional theoretical input into the problem.