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arXiv · 1801.10167

Interacting Qubit-Photon Bound States with Superconducting Circuits

Neereja M. Sundaresan·Rex Lundgren·Guanyu Zhu·Alexey V. Gorshkov·Andrew A. Houck
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Abstract

Qubits strongly coupled to a photonic crystal give rise to many exotic physical scenarios, beginning with single and multi-excitation qubit-photon dressed bound states comprising induced spatially localized photonic modes, centered around the qubits, and the qubits themselves. The localization of these states changes with qubit detuning from the band-edge, offering an avenue of in situ control of bound state interaction. Here, we present experimental results from a device with two qubits coupled to a superconducting microwave photonic crystal and realize tunable on-site and inter-bound state interactions. We observe a fourth-order two photon virtual process between bound states indicating strong coupling between the photonic crystal and qubits. Due to their localization-dependent interaction, these states offer the ability to create one-dimensional chains of bound states with tunable and potentially long-range interactions that preserve the qubits' spatial organization, a key criterion for realization of certain quantum many-body models. The widely tunable, strong and robust interactions demonstrated with this system are promising benchmarks towards realizing larger, more complex systems of bound states.

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Neereja M. Sundaresan, Rex Lundgren, Guanyu Zhu, Alexey V. Gorshkov, Andrew A. Houck. 2018-01-30. Interacting Qubit-Photon Bound States with Superconducting Circuits. https://doi.org/10.1103/physrevx.9.011021

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