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arXiv · 1205.3877

Null Values and Quantum State Discrimination

Oded Zilberberg·Alessandro Romito·David J. Starling·Gregory A. Howland·Curtis J. Broadbent·John C. Howell·Yuval Gefen
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Abstract

We present a measurement protocol for discriminating between two different quantum states of a qubit with high fidelity. The protocol, called null value, is comprised of a projective measurement performed on the system with a small probability (also known as partial-collapse), followed by a tuned postselection. We report on an optical experimental implementation of the scheme. We show that our protocol leads to an amplified signal-to-noise ratio (as compared with a straightforward strong measurement) when discerning between the two quantum states.

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Oded Zilberberg, Alessandro Romito, David J. Starling, Gregory A. Howland, Curtis J. Broadbent, John C. Howell, Yuval Gefen. 2012-05-17. Null Values and Quantum State Discrimination. https://doi.org/10.1103/physrevlett.110.170405

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