title: Correlated Emission Lasing in Harmonic Oscillators Coupled via a Single Three-Level Artificial Atom.
abstract: A single superconducting artificial atom can be used for coupling electromagnetic fields up to the single-photon level due to an easily achieved strong coupling regime. Bringing a pair of harmonic oscillators into resonance with the transitions of a three-level atom converts atomic spontaneous processes into correlated emission dynamics. We present the experimental demonstration of two-mode correlated emission lasing in harmonic oscillators coupled via a fully controllable three-level superconducting quantum system (artificial atom). The correlation of emissions with two different colors reveals itself as equally narrowed linewidths and quenching of their mutual phase diffusion. The mutual linewidth is more than 4 orders of magnitude narrower than the Schawlow-Townes limit. The interference between the different color lasing fields demonstrates that the two-mode fields are strongly correlated.
authors.affiliation: Center for Emergent Matter Science, RIKEN, Wako, Saitama 351-0198, Japan.|Physics Department, Royal Holloway, University of London, Egham, Surrey TW20 0EX, United Kingdom.
authors.forename: Z H
authors.initials: ZH
authors.lastname: Peng
authors.affiliation: Institute of Microelectronics, Tsinghua University, Beijing 100084, China.|Tsinghua National Laboratory for Information Science and Technology (TNList), Beijing 100084, China.
authors.forename: Yu-Xi
authors.initials: YX
authors.lastname: Liu
authors.affiliation: Center for Emergent Matter Science, RIKEN, Wako, Saitama 351-0198, Japan.
authors.forename: J T
authors.initials: JT
authors.lastname: Peltonen
authors.affiliation: NEC Smart Energy Research Laboratories, Tsukuba, Ibaraki 305-8501, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Center for Emergent Matter Science, RIKEN, Wako, Saitama 351-0198, Japan.|Department of Physics, Tokyo University of Science, Kagurazaka, Tokyo 162-8601, Japan.
authors.forename: J S
authors.initials: JS
authors.lastname: Tsai
authors.affiliation: Center for Emergent Matter Science, RIKEN, Wako, Saitama 351-0198, Japan.|Physics Department, Royal Holloway, University of London, Egham, Surrey TW20 0EX, United Kingdom.|National Physical Laboratory, Teddington, TW11 0LW, United Kingdom.|Moscow Institute of Physics and Technology, Dolgoprudny, 141700, Russia.
authors.forename: O
authors.initials: O
authors.lastname: Astafiev