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arXiv · 1412.6525

Preserving photon qubits in an unknown quantum state with Knill Dynamical Decoupling - Towards an all optical quantum memory

Manish K. Gupta·Erik J. Navarro·Todd A. Moulder·Jason D. Mueller·Ashkan Balouchi·Katherine L. Brown·Hwang Lee·Jonathan P. Dowling
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Abstract

The implementation of polarization-based quantum communication is limited by signal loss and decoherence caused by the birefringence of a single-mode fiber. We investigate the Knill dynamical decoupling scheme, implemented using half-wave plates, to minimize decoherence and show that a fidelity greater than $99\%$ can be achieved in absence of rotation error and fidelity greater than $96\%$ can be achieved in presence of rotation error. Such a scheme can be used to preserve any quantum state with high fidelity and has potential application for constructing all optical quantum delay line, quantum memory, and quantum repeater.

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Manish K. Gupta, Erik J. Navarro, Todd A. Moulder, Jason D. Mueller, Ashkan Balouchi, Katherine L. Brown, Hwang Lee, Jonathan P. Dowling. 2014-12-19. Preserving photon qubits in an unknown quantum state with Knill Dynamical Decoupling - Towards an all optical quantum memory. https://doi.org/10.1103/physreva.91.032329

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