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Taming Entanglement

Paul Kwiat·Joe Altepeter·David Branning·Evan Jeffrey·Nicholas Peters·Tzu-Chieh Wei
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Abstract

Using a spontaneous parametric-downconversion source of photon pairs, we are working towards the creation of arbitrary 2-qubit quantum states with high fidelity. Currently, all physically allowable combinations of polarization entanglement and mixture can be produced, including maximally-entangled mixed states. The states are experimentally measured and refined via computer-automated quantum-state tomography, and this system has also been used to perform single-qubit and ancilla-assisted quantum process tomography.

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Paul Kwiat, Joe Altepeter, David Branning, Evan Jeffrey, Nicholas Peters, Tzu-Chieh Wei. 2003-03-07. Taming Entanglement. https://arxiv.org/abs/quant-ph/0303040

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