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arXiv · 1806.00182

Nonreciprocity realized with quantum nonlinearity

Andrés Rosario Hamann·Clemens Müller·Markus Jerger·Maximilian Zanner·Joshua Combes·Mikhail Pletyukhov·Martin Weides·Thomas M. Stace·Arkady Fedorov
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Abstract

Nonreciprocal devices are a key element for signal routing and noise isolation. Rapid development of quantum technologies has boosted the demand for a new generation of miniaturized and low-loss nonreciprocal components. Here we use a pair of tunable superconducting artificial atoms in a 1D waveguide to experimentally realize a minimal passive nonreciprocal device. Taking advantage of the quantum nonlinear behavior of artificial atoms, we achieve nonreciprocal transmission through the waveguide in a wide range of powers. Our results are consistent with theoretical modeling showing that nonreciprocity is associated with the population of the two-qubit nonlocal entangled quasi-dark state, which responds asymmetrically to incident fields from opposing directions. Our experiment highlights the role of quantum correlations in enabling nonreciprocal behavior and opens a path to building passive quantum nonreciprocal devices without magnetic fields.

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Andrés Rosario Hamann, Clemens Müller, Markus Jerger, Maximilian Zanner, Joshua Combes, Mikhail Pletyukhov, Martin Weides, Thomas M. Stace, Arkady Fedorov. 2018-06-01. Nonreciprocity realized with quantum nonlinearity. https://doi.org/10.1103/physrevlett.121.123601

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