Full Bloch sphere teleportation of spinor Bose-Einstein condensates and spin ensembles

TL;DR

This paper presents a generalized quantum teleportation protocol for spin coherent states on the Bloch sphere, enabling transfer of states with arbitrary orientations and surpassing classical and estimation bounds.

Contribution

The authors extend a previous teleportation scheme to arbitrary Bloch sphere states, allowing full Bloch sphere teleportation of spinor Bose-Einstein condensates and spin ensembles.

Findings

Protocol breaks classical communication bounds.

Enables teleportation of states with large deviations from polarization.

Surpasses quantum state estimation with postselection.

Abstract

Quantum teleportation is the transfer of quantum information between two locations by the use of shared entanglement. Current teleportation schemes broadly fall under one of two categories, of either qubit or continuous variables teleportation. Spin coherent states on spin ensembles can be teleported under the continuous variables approximation for states with small deviations from a given polarization. However, for spin coherent states with large deviations, no convenient teleportation protocol exists. Recently, we introduced a teleportation scheme where a spin coherent state lying on the equator of the Bloch sphere is teleported between distant parties (A.N. Pyrkov and T. Byrnes, New. J. Phys. 16, 073038 (2014)). Here we generalize the protocol to a spin coherent state with an arbitrary position on Bloch sphere. Our proposed scheme breaks classical bounds based on communication in the unconditional case and quantum state estimation with postselection.