Quantum Nonlocality for Continuous Variable

초록

Nonlocality for continuous variable systems have been studied by using Clauser-Horne-Shimony-Holt(CHSH) inequality with highly degenerate dichotomic observables. It was shown that local party measurements lead the CHSH Bell function to be represented by Wigner functions, which are commonly adopted to study quantum optical features. Even though the approach enables to show the nonlocality, it exhibits only the partial violation of CHSH inequality. Recently, Chen et al. showed that the maximal violation can be achieved it employing "pseudospin" observable. However, the "psedospin" observables are not known to be realized for a quantum optical system. In this work, we suggest experimentally feasible observables, based on photon number and investigate the quantum nonlocality for two-mode squeezed state.