Quantum teleportation with close-to-maximal entanglement from a beam splitter

Olivier Pfister

隆輔 大倉, Noboru Watanabe

Ying Xia, Huan Zhang, Shoukang Chang +3 more

Ngoc-Khanh Tran, Olivier Pfister

We investigate theoretically quantum teleportation by means of the number-sum and phase-difference variables. We show that a unitary beam-splitter transformation turns two-mode Fock-states into close-to-maximally entangled states, in this case close approximations of the relative-phase eigenstates. These states could be created experimentally using on-demand single-photon sources, but also with any second-quantized bosonic system (e.g., trapped ions, Bose-Einstein condensates). We show that such ``quasi-EPR'' states can yield near-unity fidelity for the teleportation of coherent states and of ``Schr\"odinger cat'' states.

Haleema Sadia Qureshi, Shakir Ullah, Fazal Ghafoor

Abstract We theoretically implement the protocol of continuous variable quantum teleportation wherein Alice and Bob share a state built by a linear beam splitter as general two-mode Gaussian entangled state. Using the non-classicality and purity of the two single-mode Gaussian states employed initially at the input of the beam splitter, the unknown state teleportation protocol is explicitly implemented in terms of squeezing and phase space quadratures. We show that fidelity of the teleported state is maximal when the gain factor g is equal to 1 and gradually decreases when g deviates from 1 on either side. We further find that teleportation fidelity decreases when one of the input states of the beam splitter is replaced by the state of thermal photons.

Karl‐Heinz Fichtner, Masanori Ohya