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Measurement-Based Teleportation Along Quantum Spin Chains

J. P. Barjaktarevic·J. Links·G. J. Milburn·Ross H. McKenzie
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Abstract

We consider teleportation of an arbitrary spin-1/2 target quantum state along the ground state of a quantum spin chain. We present a decomposition of the Hilbert space of the many body quantum state into 4 vector spaces. Within each of these subspaces, it is possible to take any superposition of states, and use projective measurements to perform unit fidelity teleportation. Any such superposition is necessarily a spin liquid state. We also show that all total spin-0 quantum states belong in the same space, so that it is possible to perform unit fidelity teleportation over any one-dimensional spin-0 many body quantum state. We generalise to $n$-Bell states, and present some general bounds on fidelity of teleportation given a general state of a quantum spin chain.

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J. P. Barjaktarevic, J. Links, G. J. Milburn, Ross H. McKenzie. 2005-03-09. Measurement-Based Teleportation Along Quantum Spin Chains. https://doi.org/10.1103/physrevlett.95.230501

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