Interacting Qubit-Photon Bound States with Superconducting Circuits

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

Research output: Contribution to journalArticlepeer-review

63 Scopus citations


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

Original languageEnglish (US)
Article number011021
JournalPhysical Review X
Issue number1
StatePublished - Feb 1 2019

All Science Journal Classification (ASJC) codes

  • General Physics and Astronomy


Dive into the research topics of 'Interacting Qubit-Photon Bound States with Superconducting Circuits'. Together they form a unique fingerprint.

Cite this