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arXiv · 0906.0270

Superdense coding using the quantum superposition principle

Dipankar Home·A. K. Pan·S. Adhikari·A. S. Majumdar·M. A. B. Whitaker
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Abstract

By sending a classical two-level system, one can transfer information about only \emph{two} distinguishable outcomes. Here we show that in quantum mechanics, using both the spin and path degrees of freedom of a spin-1/2 particle, and a Mach-Zehnder type interferometric arrangement with two suitable Stern-Gerlach detectors, it is possible to transfer information about \emph{four} distinguishable outcomes. This procedure does \emph{not} require using quantum entanglement as a resource as in the well-known protocol of dense coding, but instead hinges entirely on the quantum superposition principle. We also study probabilistic dense coding using our set-up and show that the dense coding scheme using quantum superposition cannot be optimized any further by extending the interferometric arrangement with more beam splitters.

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Dipankar Home, A. K. Pan, S. Adhikari, A. S. Majumdar, M. A. B. Whitaker. 2009-06-01. Superdense coding using the quantum superposition principle. https://arxiv.org/abs/0906.0270

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