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Precise Creation, Characterization, and Manipulation of Single Optical Qubits

Nicholas Peters·Joseph Altepeter·Evan Jeffrey·David Branning·Paul Kwiat
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Abstract

We present the theoretical basis for and experimental verification of arbitrary single-qubit state generation, using the polarization of photons generated via spontaneous parametric downconversion. Our precision measurement and state reconstruction system has the capability to distinguish over 3 million states, all of which can be reproducibly generated using our state creation apparatus. In order to complete the triumvirate of single qubit control, there must be a way to not only manipulate single qubits after creation and before measurement, but a way to characterize the manipulations \emph{themselves}. We present a general representation of arbitrary processes, and experimental techniques for generating a variety of single qubit manipulations, including unitary, decohering, and (partially) polarizing operations.

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Nicholas Peters, Joseph Altepeter, Evan Jeffrey, David Branning, Paul Kwiat. 2005-02-27. Precise Creation, Characterization, and Manipulation of Single Optical Qubits. https://arxiv.org/abs/quant-ph/0502177

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