Print Email Facebook Twitter Multi-mode ultra-strong coupling in circuit quantum electrodynamics Title Multi-mode ultra-strong coupling in circuit quantum electrodynamics Author Bosman, S.J. (TU Delft QN/Steele Lab; Kavli institute of nanoscience Delft) Gely, M.F. (TU Delft QN/Steele Lab; Kavli institute of nanoscience Delft) Singh, Vibhor (Indian Institute of Science) Bruno, A. (TU Delft QCD/DiCarlo Lab; TU Delft QuTech Advanced Research Centre) Bothner, D. (TU Delft QN/Steele Lab; Kavli institute of nanoscience Delft) Steele, G.A. (TU Delft QN/Steele Lab; Kavli institute of nanoscience Delft) Date 2017-12-01 Abstract With the introduction of superconducting circuits into the field of quantum optics, many experimental demonstrations of the quantum physics of an artificial atom coupled to a single-mode light field have been realized. Engineering such quantum systems offers the opportunity to explore extreme regimes of light-matter interaction that are inaccessible with natural systems. For instance the coupling strength g can be increased until it is comparable with the atomic or mode frequency ωa,m and the atom can be coupled to multiple modes which has always challenged our understanding of light-matter interaction. Here, we experimentally realize a transmon qubit in the ultra-strong coupling regime, reaching coupling ratios of g/ωm = 0.19 and we measure multi-mode interactions through a hybridization of the qubit up to the fifth mode of the resonator. This is enabled by a qubit with 88% of its capacitance formed by a vacuum-gap capacitance with the center conductor of a coplanar waveguide resonator. In addition to potential applications in quantum information technologies due to its small size, this architecture offers the potential to further explore the regime of multi-mode ultra-strong coupling. To reference this document use: http://resolver.tudelft.nl/uuid:5f83dab2-d9fb-468e-8e11-b19cb0d82c36 DOI https://doi.org/10.1038/s41534-017-0046-y ISSN 2056-6387 Source NPJ Quantum Information, 3 (1), 1-6 Part of collection Institutional Repository Document type journal article Rights © 2017 S.J. Bosman, M.F. Gely, Vibhor Singh, A. Bruno, D. Bothner, G.A. Steele Files PDF s41534_017_0046_y.pdf 2.02 MB Close viewer /islandora/object/uuid:5f83dab2-d9fb-468e-8e11-b19cb0d82c36/datastream/OBJ/view