Improvement on teleportation of continuous variables by photon subtractionvia conditional measurement - art. no. 032302

We show that the recently proposed scheme of teleportation of continuous va riables [S.L. Braunstein and H.J. Kimble, Phys. Rev. Lett. 80, 869 (1998)] can be improved by a conditional measurement of the entangled state shared by the sender and the recipient. The conditional measurement subtracts phot ons from the original entangled two-mode squeezed vacuum, by transmitting e ach mode through a low-reflectivity beam splitter and performing a joint ph oton-number measurement on the reflected beams. In this way the degree of e ntanglement of the shared state is increased and so is the fidelity of the teleported state.