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