We propose an experimental procedure to directly measure the state of an electromagnetic field inside a resonator, corresponding to a superconducting transmission line, coupled to a Cooper-pair box (CPB). The measurement protocol is based on the use of a dispersive interaction between the field and the CPB, and the coupling to an external classical field that is tuned to resonance with either the field or the CPB. We present a numerical simulation that demonstrates the feasibility of this protocol, which is within reach of present technology.
We report the observation of Electromagnetically Induced Transparency (EIT) of a mechanical field, where a superconducting artificial atom is coupled to a 1D-transmission line for surface acoustic waves. An electromagnetic microwave drive is used as the control field, rendering the superconducting transmon qubit transparent to the acoustic probe beam. The strong frequency dependence of the acoustic coupling enables EIT in a ladder configuration due to the suppressed relaxation of the upper level. Our results show that superconducting circuits can be engineered to interact with acoustic fields …
Improving the accuracy of circuit quantization using the electromagnetic properties of superconductors
Seoul National University（首尔大学）；Korea Research Institute of Standards and Science（韩国标准科学研究院）；Quantum Devices Labs, Korea Advanced Nano Fab Center（韩国先进纳米制造中心量子器件实验室）；Quantum Design Korea（量子设计韩国公司）；SKKU Adavanced Institute of Nanotechnology, Sungkyunkwan University（成均馆大学SKKU纳米技术高级研究所）
We report a theoretical study of the electromagnetic waves (EWs) propagation through an array of superconducting qubits, i.e. coherent two-level systems, embedded in a low-dissipative transmission line. We focus on the near-resonant case as the frequency of EWs $ω\simeq ω_q$, where $ω_q$ is the qubit frequency. In this limit we derive the effective dynamic nonlinear wave equation allowing one to obtain the frequency dependent transmission coefficient of EWs, $D(ω)$. In the linear regime and a relatively wide frequency region we obtain a strong resonant suppression of $D(ω)$ in both cases of a …
We propose a traveling wave scheme for broadband microwave isolation using parametric mode conversion in conjunction with adiabatic phase matching technique in a pair of coupled nonlinear transmission lines. This scheme is compatible with the circuit quantum electrodynamics architecture (cQED) and provides isolation without introducing additional quantum noise. We first present the scheme in a general setting then propose an implementation with Josephson junction transmission lines. Numerical simulation shows more than 20 dB isolation over an octave bandwidth (4-8\,GHz) in a 2000 unit cell dev…
Superconducting metamaterials are a promising resource for quantum information science. In the context of circuit QED, they provide a means to engineer on-chip, novel dispersion relations and a band structure that could ultimately be utilized for generating complex entangled states of quantum circuitry, for quantum reservoir engineering, and as an element for quantum simulation architectures. Here we report on the development and measurement at millikelvin temperatures of a particular type of circuit metamaterial resonator composed of planar superconducting lumped-element reactances in the for…
The study of quantum heat transport in superconducting circuits is significant for further understanding the connection between quantum mechanics and thermodynamics, and for possible applications for quantum information. The first experimental realisations of devices demonstrating photonic heat transport mediated by a qubit have already been designed and measured. Motivated by the analysis of such experimental results, and for future experimental designs, we numerically evaluate the photonic heat transport of qubit-resonator devices in the linear circuit regime through electromagnetic simulati…
We demonstrate how heating of an environment can invert the line shape of a driven cavity. We consider a superconducting coplanar cavity coupled to multiple artificial atoms. The measured cavity transmission is characterized by Fano-type resonances with a shape that is continuously tunable by bias current through nearby (magnetic flux) control lines. In particular, the same dispersive shift of the microwave cavity can be observed as a peak or a dip. We find that this Fano-peak inversion is possible due to a tunable interference between a microwave transmission through a background, with reacti…
From coherent to fermionized microwave photons in a superconducting transmission line
Pitaevskii BEC Center, INO-CNR and Dipartimento di Fisica, Università di Trento（彭尼夫斯基玻色-爱因斯坦凝聚中心，意大利国家研究委员会材料研究所和特伦托大学物理系）；INFN-TIFPA, Trento Institute for Fundamental Physics and Applications（INFN-TIFPA，特伦托基础物理与应用研究所）
Extracting Electromagnetic Bare Mode Couplings in Large Superconducting Quantum Processors
Google Quantum AI（谷歌量子人工智能）；Purdue Quantum Science and Engineering Institute, Purdue University（普渡大学量子科学与工程研究所）；Department of Physics, University of California, Santa Barbara（加州大学圣塔芭芭拉分校物理系）
Causal signal transmission by quantum fields. Electromagnetic interaction of distinguishable devices and the optical equivalence theorem
旋转波近似之外的电磁相互作用的广义相空间技术[L.P.和S.S.，arXiv：1104.3825（2011）]应用于可区分设备的交互。这篇论文是建立在“做量子电动力学，同时思考经典”的概念，这是一个推广的Sudarshan著名的光学等效定理[E.C.G. Sudarshan，Phys. Rev. Lett. 10，277（1963）]到相互作用的电磁场。这个概念允许人们将固有的量子问题简化为半经典问题。
Emitters strongly coupled to a photonic crystal provide a powerful platform for realizing novel quantum light-matter interactions. Here we study the optical properties of a three-level artificial atomic chain coupled to a one-dimensional superconducting microwave photonic crystal. A sharp minimum-energy dip appears in the transmission spectrum of a weak input field, which reveals rich behavior of the long-range interactions arising from localized bound states. We find that the dip frequency scales linearly with both the number of the artificial atoms and the characteristic strength of the long…
The dynamics of a weakly anharmonic superconducting qubit in a complex electromagnetic environment is generally well-described by an effective multimode Kerr Hamiltonian at sufficiently weak excitation. This Hamiltonian can be embedded in a master equation with losses determined by the details of the electromagnetic environment. Recent experiments indicate, however, that when a superconducting circuit is driven with microwave signals the observed relaxation rates appear to be substantially different from expectations based on the electromagnetic environment of the qubit alone. This issue is a …
We present a one-step scheme to construct the controlled-phase gate deterministically on remote transmon qutrits coupled to different resonators connected by a superconducting transmission line for an universal distributed quantum computing. Different from previous works on remote superconducting qubits, the present gate is implemented with coherent evolutions of the entire system in the all-resonance regime assisted by the dark photons to robust against the transmission line loss, which allows the possibility of the complex designation of a long-length transmission line to link lots of circui…
Fluxon Time-Delay Readout of a Superconducting Qubit Protected by a Spectral Gap in a Josephson Transmission Line
Secure System Platform Research Laboratories, NEC Corporation（NEC公司安全系统平台研究实验室）；NEC-AIST Quantum Technology Cooperative Research Laboratory（NEC-AIST量子技术联合研究实验室）；Division of Physics, Faculty of Pure and Applied Sciences, University of Tsukuba（筑波大学理学院物理学系）；Graduate School of Engineering, Nagoya University（名古屋大学研究生院工学研究科）；Global Research and Development Center for Business by Quantum-AI technology (G-QuAT), National Institute of Advanced Industrial Science and Technology (AIST)（国立产业技术综合研究所量子AI技术商业化全球研发中心（G-QuAT））
Optomechanical analog of two-color electromagnetically-induced transparency: Photon transmission through an optomechanical device with a two-level system
Analog quantum simulation of $ϕ^4$ field theory with a superconducting transmission line
Massachusetts Institute of Technology（麻省理工学院）；Research Laboratory of Electronics, Massachusetts Institute of Technology（麻省理工学院电子研究实验室）；Center for Theoretical Physics - a Leinweber Institute, Massachusetts Institute of Technology（麻省理工学院莱因韦伯理论物理中心）；Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology（麻省理工学院电气工程和计算机科学系）；Physics Division, Argonne National Laboratory（阿贡国家实验室物理部）；Air Force Research Laboratory, Information Directorate（空军研究实验室信息管理局）
