Remote state preparation and teleportation in phase space

Continuous variable remote state preparation and teleportation are analysed using Wigner functions in phase space. We suggest a remote squeezed state preparation scheme between two parties sharing an entangled twin beam, where homodyne detection on one beam is used as a conditional source of squeezing for the other beam. The scheme also works with noisy measurements, and provides squeezing if the homodyne quantum efficiency is larger than 50%. The phase space approach is shown to provide a convenient framework to describe teleportation as a generalized conditional measurement, and to evaluate relevant degrading effects, such the finite amount of entanglement, the losses along the line and the nonunit quantum efficiency at the sender location.

[1]  Kevin Cahill,et al.  Ordered Expansions in Boson Amplitude Operators , 1969 .

[2]  Kevin Cahill,et al.  DENSITY OPERATORS AND QUASIPROBABILITY DISTRIBUTIONS. , 1969 .

[3]  Kumar,et al.  Pulsed twin beams of light. , 1990, Physical review letters.

[4]  Charles H. Bennett,et al.  Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels. , 1993, Physical review letters.

[5]  Paul,et al.  Realistic optical homodyne measurements and quasiprobability distributions. , 1993, Physical review. A, Atomic, molecular, and optical physics.

[6]  Optimized phase detection , 1995 .

[7]  P. Busch,et al.  The complementarity of quantum observables: Theory and experiments , 1995 .

[8]  K. Peng,et al.  Fourth International Conference on Squeezed States and Uncertainty Relations , 1996 .

[9]  Phase space distributions from three-port couplers , 1996, quant-ph/9611034.

[10]  M. Paris.  Joint generation of identical squeezed states , 1997 .

[11]  Kimble,et al.  Unconditional quantum teleportation , 1998, Science.

[12]  Dijet event rates in deep inelastic scattering at HERA , 1998, hep-ex/9806029.

[13]  A. Pati.  Minimum classical bit for remote preparation and measurement of a qubit , 1999, quant-ph/9907022.

[14]  Akira Furusawa,et al.  Fidelity and information in the quantum teleportation of continuous variables , 2000, quant-ph/0003053.

[15]  H. Lo.  Classical-communication cost in distributed quantum-information processing: A generalization of quantum-communication complexity , 1999, quant-ph/9912009.

[16]  Dichromatic squeezing generation , 2001 .