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arXiv · 0909.0425

Swapping path-spin intraparticle entanglement onto spin-spin interparticle entanglement

S. Adhikari·A. S. Majumdar·Dipankar Home·Alok Kumar pan
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Abstract

Based on a scheme that produces an entanglement between the spin and the path variables of a single spin-1/2 particle (qubit) using a beam-splitter and a spin-flipper, we formulate a procedure for transferring this intraparticle hybrid entanglement to an interparticle entanglement between the spin variables of two other spatially separated spin-1/2 particles which never interact with each other during the entire process. This procedure of entanglement swapping is accomplished by a Mach-Zehnder setup in conjunction with the Stern-Gerlach measuring device, using suitable unitary operations. The proposed protocol, thus, enables the use of intraparticle entanglement as a resource - a feature that has remained unexplored.

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S. Adhikari, A. S. Majumdar, Dipankar Home, Alok Kumar pan. 2010-02-19. Swapping path-spin intraparticle entanglement onto spin-spin interparticle entanglement. https://doi.org/10.1209/0295-5075%2F89%2F10005

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