title: Single microwave-photon detector using an artificial Λ-type three-level system.
abstract: Single-photon detection is a requisite technique in quantum-optics experiments in both the optical and the microwave domains. However, the energy of microwave quanta are four to five orders of magnitude less than their optical counterpart, making the efficient detection of single microwave photons extremely challenging. Here we demonstrate the detection of a single microwave photon propagating through a waveguide. The detector is implemented with an impedance-matched artificial Λ system comprising the dressed states of a driven superconducting qubit coupled to a microwave resonator. Each signal photon deterministically induces a Raman transition in the Λ system and excites the qubit. The subsequent dispersive readout of the qubit produces a discrete 'click'. We attain a high single-photon-detection efficiency of 0.66±0.06 with a low dark-count probability of 0.014±0.001 and a reset time of ∼400 ns. This detector can be exploited for various applications in quantum sensing, quantum communication and quantum information processing.
authors.affiliation: RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198, Saitama, Japan.
authors.forename: Kunihiro
authors.identifier: 0000-0002-1151-4512
authors.initials: K
authors.lastname: Inomata
authors.affiliation: RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198, Saitama, Japan.
authors.forename: Zhirong
authors.initials: Z
authors.lastname: Lin
authors.affiliation: College of Liberal Arts and Sciences, Tokyo Medical and Dental University, Ichikawa 272-0827, Chiba, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Koshino
authors.affiliation: MIT Lincoln Laboratory, Lexington, Massachusetts 02420, USA.|Departent of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: William D
authors.initials: WD
authors.lastname: Oliver
authors.affiliation: RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198, Saitama, Japan.|Department of Physics, Tokyo University of Science, Shinjuku-ku, Tokyo 162-8601, Japan.
authors.forename: Jaw-Shen
authors.initials: JS
authors.lastname: Tsai
authors.affiliation: NEC IoT Device Research Laboratories, Tsukuba 305-8501, Ibaraki, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198, Saitama, Japan.|Research Center for Advanced Science and Technology (RCAST), The University of Tokyo, Meguro-ku, Tokyo 153-8904, Japan.
authors.forename: Yasunobu
authors.initials: Y
authors.lastname: Nakamura