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Related papers: Josephson Amplifier for Qubit Readout

200 papers

We report the parametric amplification of a microwave signal in a Kerr medium formed from superconducting qubits. Two mutually coupled flux qubits, embedded in the current antinode of a superconducting coplanar waveguide resonator, are used…

Superconductivity · Physics 2015-06-18 M. Rehak , P. Neilinger , M. Grajcar , G. Oelsner , U. Hubner , E. Ilichev , H. -G. Meyer

Single-mode Josephson junction-based parametric amplifiers are often modeled as perfect amplifiers and squeezers. We show that, in practice, the gain, quantum efficiency, and output field squeezing of these devices are limited by usually…

We demonstrate a 3-port Josephson parametric circulator, matched to 50 Ohm using second order Chebyshev networks. The device notably operates with two of its signal ports at the same frequency and uses only two out-of-phase pumps at a…

Quantum Physics · Physics 2023-05-31 Randy Kwende , Theodore White , Ofer Naaman

Superconducting quantum circuits based on Josephson junctions have made rapid progress in demonstrating quantum behavior and scalability. However, the future prospects ultimately depend upon the intrinsic coherence of Josephson junctions,…

Detection of low-reflectivity objects can be enriched via the so-called quantum illumination procedure. In order that this quantum procedure outperforms classical detection protocols, entangled states of microwave radiation are initially…

This paper presents a detailed theoretical review of the amplification process in Josephson Parametric Amplifiers (JPAs), which are crucial for quantum-limited signal amplification in superconducting circuits. The paper begins by outlining…

Quantum Physics · Physics 2025-07-31 Rajlaxmi Bhoite , Shraddhanjali Choudhury

The axion is a hypothetical particle, a promising candidate for dark matter, and a solution to the strong CP problem. Axion haloscope search experiments deal with a signal power comparable to noise uncertainty at millikelvin temperature. We…

We present a novel readout scheme for phase qubits which eliminates the read-out SQUID so that the entire qubit and measurement circuitry only requires a single Josephson junction. Our scheme capacitively couples the phase qubit directly to…

We demonstrate a high-frequency generator operating at ~200GHz based on flipping a semifluxon in a Josephson junction of moderate normalized length. The semifluxon spontaneously appears at the $\pi$ discontinuity of the Josephson phase…

Superconductivity · Physics 2014-02-14 M. Paramonov , M. Yu. Fominsky , V. P. Koshelets , B. Neumeier , D. Koelle , R. Kleiner , E. Goldobin

Qubits on solid state devices could potentially provide the rapid control necessary for developing scalable quantum information processors. Materials innovation and design breakthroughs have increased functionality and coherence of qubits…

We present measurements of an amplifier based on a dc superconducting quantum interference device (SQUID) with submicron Al-AlOx-Al Josephson junctions. The small junction size reduces their self-capacitance and allows for the use of…

Superconductivity · Physics 2015-05-19 M. P. DeFeo , P. Bhupathi , K. Yu , T. W. Heitmann , C. Song , R. McDermott , B. L. T. Plourde

Superconducting traveling-wave parametric amplifiers have emerged as highly promising devices for near-quantum-limited broadband amplification of microwave signals and are essential for high quantum-efficiency microwave readout lines.…

The ability to non-dissipatively tune the Josephson coupling energy of Josephson junctions is a useful tool in frequency-tunable qubits. This is typically done by threading magnetic flux through two junctions connected in a loop, a geometry…

Mesoscale and Nanoscale Physics · Physics 2026-02-26 Maxwell Wisne , Venkat Chandrasekhar

In this article we present an experimental study of microwave resonators made out of Josephson junctions. The junctions are embedded in a transmission line geometry so that they increase the inductance per length for the line. By comparing…

Mesoscale and Nanoscale Physics · Physics 2023-09-20 Antti Ranni , Harald Havir , Subhomoy Haldar , Ville F. Maisi

Josephson superconducting qubits and parametric amplifiers are prominent examples of superconducting quantum circuits that have shown rapid progress in recent years. With the growing complexity of such devices, the requirements for…

The accuracy of microwave measurements is not only critical for applications in telecommunication and radar, but also for future quantum computers. Qubit technologies such as superconducting qubits or spin qubits require detecting minuscule…

Quantum Physics · Physics 2023-03-14 N. Crescini , E. G. Kelly , G. Salis , A. Fuhrer

We propose a new type of cryogenic current amplifiers, in which low-frequency power spectrum of current can be measured through a measurement of microwave response of a superconducting resonant circuit shunted by a series array of Josephson…

Instrumentation and Detectors · Physics 2015-08-14 Yuma Okazaki , Nobu-hisa Kaneko

We develop the concept of quasi-phasematching (QPM) by implementing it in the recently proposed Josephson traveling-wave parametric amplifier (JTWPA) with three-wave mixing (3WM). The amplifier is based on a ladder transmission line…

Superconductivity · Physics 2021-06-02 A. B. Zorin

Superconducting parametric amplifiers have great promise for quantum-limited readout of superconducting qubits and detectors. Until recently, most superconducting parametric amplifiers had been based on resonant structures, limiting their…

Superconductivity · Physics 2015-01-13 Saptarshi Chaudhuri , Jiansong Gao , Kent Irwin