Nonlocal Measurements and Teleportation of Quantum States

Juan Bai, Qi Guo, Liu‐Yong Cheng +4 more

We propose a protocol to implement the nonlocal Bell-state measurement, which is nearly determinate with the help of weak cross-Kerr nonlinearities and quantum non-destructive photon number resolving detection. Based on the nonlocal Bell-state measurement, we implement the quantum information transfer from one place to another. The process is different from conventional teleportation but can be regarded as a novel form of teleportation without entangled channel and classic communication.

Nicolas Gisin

Lev Vaidman A

The recent result of Bennett et al. [Phys. Rev. Lett. 70, 1895 (1993)] of teleportation of an unknown quantum state is obtained in the framework of nonlocal measurements proposed by Aharonov and Albert [Phys. Rev. D 21, 3316 (1980); 24, 359 (1981)]. The latter method is generalized to the teleportation of a quantum state of a system with continuous variables.

Dirk Bouwmeester, Klaus Mattle, Jian-Wei Pan +3 more

Sandu Popescu, Nicolas Gisin

Sergey A. Fedorov, Emil Zeuthen

Regular measurements allow predicting the future and retrodicting the past of quantum systems. Time-nonlocal measurements can leave the future and the past uncertain, yet establish a relation between them. We show that continuous time-nonlocal measurements can be used to transfer a quantum state via teleportation or direct transmission. Considering two oscillators probed by traveling fields, we analytically identify strategies for performing the state transfer perfectly across a wide range of linear oscillator-field interactions beyond the pure beam-splitter and two-mode-squeezing types.