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International Conference on Quantum Information

Unambiguous preparation of non-orthogonal quantum states

Fabian A. Torres-Ruiz, J. Aguirre, A. Delgado, G. Lima, Sebastião Pádua, Luis Roa, C. Saavedra

Published Jan 1, 2008• 0 citations
Publisher

Abstract

A probabilistic method for the unambiguous preparation of non-orthogonal polarization states is proposed. We show experimentally how this protocol is implemented by using two-photon states generated in the process of down conversion.
DOI
10.1364/icqi.2008.qwc2

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A probabilistic method for the unambiguous modification of non-orthogonal quantum states is proposed. This is based on conclusive modifications of the inner product between two pure quantum states in a discrimination-like process. We experimentally implemented this protocol by using two-photon polarization states generated in the process of spontaneous parametric down conversion. In the experiment, for codifying initial quantum states, we consider single photon states and heralded detection. As application, we show that when our protocol is applied to partially entangled states it allows a fine control of the amount of entanglement of the modified states.
In this paper we propose a probabilistic method which allows an unambiguous modification of two nonorthogonal quantum states. We experimentally implement this protocol by using two-photon polarization states generated in the process of spontaneous parametric down conversion. In the experiment, for codifying initial quantum states, we consider single-photon states and heralded detection. We show that the application of this protocol to entangled states allows a fine control of the amount of entanglement of the initial state.
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