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arXiv · 0811.2654

Experimental inhibition of decoherence on flying qubits via bang-bang control

Sajeev Damodarakurup·Marco Lucamarini·Giovanni Di Giuseppe·David Vitali·Paolo Tombesi
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Abstract

Decoherence may significantly affect the polarization state of optical pulses propagating in dispersive media because of the unavoidable presence of more than a single frequency in the envelope of the pulse. Here we report on the suppression of polarization decoherence in a ring cavity obtained by properly retooling for photonic qubits the ``bang-bang'' protection technique already employed for nuclear spins and nuclear-quadrupole qubits. Our results show that bang-bang control can be profitably extended to quantum information processes involving flying polarization qubits.

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Sajeev Damodarakurup, Marco Lucamarini, Giovanni Di Giuseppe, David Vitali, Paolo Tombesi. 2009-07-07. Experimental inhibition of decoherence on flying qubits via bang-bang control. https://doi.org/10.1103/physrevlett.103.040502

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