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arXiv · 1109.1762

A high-speed tunable beam splitter for feed-forward photonic quantum information processing

Xiao-song Ma·Stefan Zotter·Nuray Tetik·Angie Qarry·Thomas Jennewein·Anton Zeilinger
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Abstract

We realize quantum gates for path qubits with a high-speed, polarization-independent and tunable beam splitter. Two electro-optical modulators act in a Mach-Zehnder interferometer as high-speed phase shifters and rapidly tune its splitting ratio. We test its performance with heralded single photons, observing a polarization-independent interference contrast above 95%. The switching time is about 5.6 ns, and a maximal repetition rate is 2.5 MHz. We demonstrate tunable feed-forward operations of a single-qubit gate of path-encoded qubits and a two-qubit gate via measurement-induced interaction between two photons.

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Xiao-song Ma, Stefan Zotter, Nuray Tetik, Angie Qarry, Thomas Jennewein, Anton Zeilinger. 2011-09-08. A high-speed tunable beam splitter for feed-forward photonic quantum information processing. https://doi.org/10.1364/oe.19.022723

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