Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

IEEE Transactions on Applied Superconductivity

The AC Josephson effect and submillimeter wave mixing with a weak-link array of grain boundaries formed in YBCO film

Toshiaki Matsui, Hiroshi Ohta

Published Mar 1, 1993• 15 citations
Publisher

Abstract

The authors present a model for a series-parallel array of small metallic (nontunneling) Josephson junctions. The transmission and configuration of pair electrons between small superconducting regions are considered assuming the presence of a strong interaction between the electrostatic energy (2e)/sup 2//2C and the Josephson effect in a network of metallic weak links. The model predicts that the same behavior as that of a single junction is obtained with a superconducting weak-link device comprising multiple small superconducting regions joined by conductive bridges. In an experiment in the 100- and 320-GHz frequency ranges, the constriction of a YBCO film formed with a network of grain-boundary Josephson weak links showed that the AC Josephson effect is the same as for a single Josephson element. It is confirmed that the constriction works as a harmonic mixer at 318 GHz and that a network of high-T/sub c/ superconducting weak links can be used for a practical device operating at submillimeter-wave frequencies.>

DOI
10.1109/77.233944

Related papers

Harmonic mixing in a series array of short superconducting weak-links

Toshiaki Matsui, Bokuji Komiyama, Hiroshi Ohta

A new type of harmonic mixer using a series array of short superconducting weak-links is proposed for mixer applications at far-infrared and submillimeter-wave frequencies. The problem of limited mixer dynamic range can be eliminated by the use of a Josephson junction series array structure. Using a eleven-element series array, a preliminary experiment on harmonic mixing was carried out for two signals at 105.9 GHz and 5.4-12.6 GHz. IF (intermediate frequency) output was measured for each harmonic order from 9th to 19th by optimizing local power and bias voltage. In this experiment, 5-dB heightening of the signal-to-noise ratio was obtained at the IF output when the harmonic mixing order n was equal to the series element number, N=11.>

IEEE Transactions on Magnetics•Mar 1, 1989•3 citations

Superconducting weak links for mixing at millimeter-wave frequencies. Final report, 15 June 1970--14 June 1973

T. Van Duzer

The goals of the work were to fabricate superconductive thin-film constrictions with an electron microscope and to test them as mixers. During the grant period indium and vanadium constrictions were made with submicron dimensions and these were tested in detection and mixing modes. Most of the tests were conducted at X-band frequencies and some were done at V-band. A computer program was developed to study the theoretical behavior of a circuit model of Josephson devices such as thin-film constrictions. Considerable information was derived from the calculations and good agreement with experiments was obtained in some cases. In the process of developing sufficient understanding of electron-resist exposures, the author worked out a theory which gives general guidance for the use of electron resists for microdevice fabrication. Simple arrays of two and three devices were studied under dc conditions. A theoretical description of a generally asymmetric array was developed, taking account of the self- and mutual inductances.

•Jan 1, 1973•0 citations

THE JOSEPHSON JUNCTION AS A 100 GHz OSCILLATOR-MIXER,

Andrew Longacre, Sidney Shapiro

Abstract : The term 'Josephson effects' refers to a number of unusual properties of current flow through a barrier or weak link between two superconductors. Such a structure--called a Josephson junction--gives rise to frequency conversion effects that suggest its use as an oscillator-mixer in the millimeter and submillimeter region. Such a device would offer high sensitivity, broad bandwidth, tunability, and, in certain modes of operation, the possibility of conversion gain. These frequency conversion effects were observed in the range of 100 GHz to 600 GHz and beyond. The junctions were driven by a 75 GHz or 25 GHz klystron while coupled either to a coaxial cavity resonant at 20 GHz or to a resonance at about 500 GHz associated with the junction structure. Lines in the junction voltage-current characteristic were observed which demonstrated that, at certain values of junction bias, power at the rf--or its harmonics--was converted to power at the resonance frequency. An explanation of the experiment is given together with the necessary background, which provides the basis for a discussion of such operational considerations as upper frequency limit, sensitivity, temperature of operation, and saturation behavior at high signal levels. (Author)

•Apr 1, 1970•1 citation

Series YBCO grain boundary Josephson junctions as a terahertz harmonic mixer

Mei Yu, Haifeng Geng, Tao Hua +6 more

Abstract Josephson devices have demonstrated the capability to work as harmonic mixers at terahertz frequencies. Low temperature devices, in particular Nb–Nb point contacts have proven particularly successful. However, practical applications of these devices have been limited by the need of utilizing liquid helium. To overcome this limitation we have investigated the use of high- T c devices. In this paper, we report mixings up to the 154th harmonic at zero-bias in a series of YBa 2 Cu 3 O 7−δ (YBCO) grain boundary Josephson junctions. We have integrated a meander series of three bicrystal YBCO Josephson junctions with a log-periodic antenna. When properly operated, this configuration allows to reach a harmonic number much higher than what possible with a single junction. This shows that the mixing performance benefits from the synchronous operation which also results in an improvement of dynamic range. We believe that the integration of a higher number of phase-locked junctions may further improve the mixer’s performance. Future studies should investigate the effect of higher number of junctions on the mixer performances, as well as the effect of the meander length.

Superconductor Science and Technology•Dec 2, 2019•17 citations

Fundamental and harmonic submillimeter-wave emission from parallel Josephson junction arrays

Faouzi M. Boussaha, Morvan C. Salez, A. Féret +6 more

We report heterodyne measurements of Josephson microwave radiation emitted by a parallel array of small superconductor-insulator-superconductor (SIS) junctions at submillimeter-wave frequencies. The array consists of five Nb/Al–AlOx/Nb junctions nonevenly distributed in a niobium superconducting stripline, and is optimized for rf coupling in the 450–640 GHz range. We observed Fiske-like resonant steps in its I-V curve in the presence of magnetic field. The device was placed in a waveguide mount, and its radiation was quasioptically coupled out of the cryostat, to a SIS-mixer spectrometer in the same frequency range, with a 4–8 GHz band for spectral analysis. We detected a coherent signal in the spectra when the array was biased on the first and third steps, respectively, at the first harmonic frequency of 242 GHz and at the fundamental frequency of 493 GHz, both being the Josephson frequencies associated with their dc voltages. This strongly suggests that this type of parallel arrays optimized for wideband rf coupling, though strongly discretized, hosts dynamic fluxon regimes similar to long Josephson junctions, which could find applications in superconducting digital electronics or integrated heterodyne submillimeter-wave receivers.

Journal of Applied Physics•Apr 1, 2009•7 citations

Millimeter and submillimeter wave detection and mixing with superconducting weak links

P. L. Richards, F. Auracher, T. Van Duzer

A weak link between two bulk superconductors can exhibit Josephson effects and can be used as a fast sensitive detector or mixer for electromagnetic radiation. Emphasis is placed on the millimeter and submillimeter range where such applications are potentially most important, though such devices should also work well at lower frequencies. The peculiar properties of the weak link make possible a variety of modes of operation including one in which it is both local oscillator and mixer. These modes of operation are analyzed and the pivotal experiments are reviewed. Noise and impedance matching are considered and comparison is made with other types of detectors of millimeter and submillimeter waves.

Proceedings of the IEEE•Jan 1, 1973•41 citations
The authors present a model for a series-parallel array of small metallic (nontunneling) Josephson junctions. The transmission and configuration of pair electrons between small superconducting regions are considered assuming the presence of a strong interaction between the electrostatic energy (2e)/sup 2//2C and the Josephson effect in a network of metallic weak links. The model predicts that the same behavior as that of a single junction is obtained with a superconducting weak-link device comprising multiple small superconducting regions joined by conductive bridges. In an experiment in the 100- and 320-GHz frequency ranges, the constriction of a YBCO film formed with a network of grain-boundary Josephson weak links showed that the AC Josephson effect is the same as for a single Josephson element. It is confirmed that the constriction works as a harmonic mixer at 318 GHz and that a network of high-T/sub c/ superconducting weak links can be used for a practical device operating at submillimeter-wave frequencies.>
A new type of harmonic mixer using a series array of short superconducting weak-links is proposed for mixer applications at far-infrared and submillimeter-wave frequencies. The problem of limited mixer dynamic range can be eliminated by the use of a Josephson junction series array structure. Using a eleven-element series array, a preliminary experiment on harmonic mixing was carried out for two signals at 105.9 GHz and 5.4-12.6 GHz. IF (intermediate frequency) output was measured for each harmonic order from 9th to 19th by optimizing local power and bias voltage. In this experiment, 5-dB heightening of the signal-to-noise ratio was obtained at the IF output when the harmonic mixing order n was equal to the series element number, N=11.>
The goals of the work were to fabricate superconductive thin-film constrictions with an electron microscope and to test them as mixers. During the grant period indium and vanadium constrictions were made with submicron dimensions and these were tested in detection and mixing modes. Most of the tests were conducted at X-band frequencies and some were done at V-band. A computer program was developed to study the theoretical behavior of a circuit model of Josephson devices such as thin-film constrictions. Considerable information was derived from the calculations and good agreement with experiments was obtained in some cases. In the process of developing sufficient understanding of electron-resist exposures, the author worked out a theory which gives general guidance for the use of electron resists for microdevice fabrication. Simple arrays of two and three devices were studied under dc conditions. A theoretical description of a generally asymmetric array was developed, taking account of the self- and mutual inductances.
Abstract : The term 'Josephson effects' refers to a number of unusual properties of current flow through a barrier or weak link between two superconductors. Such a structure--called a Josephson junction--gives rise to frequency conversion effects that suggest its use as an oscillator-mixer in the millimeter and submillimeter region. Such a device would offer high sensitivity, broad bandwidth, tunability, and, in certain modes of operation, the possibility of conversion gain. These frequency conversion effects were observed in the range of 100 GHz to 600 GHz and beyond. The junctions were driven by a 75 GHz or 25 GHz klystron while coupled either to a coaxial cavity resonant at 20 GHz or to a resonance at about 500 GHz associated with the junction structure. Lines in the junction voltage-current characteristic were observed which demonstrated that, at certain values of junction bias, power at the rf--or its harmonics--was converted to power at the resonance frequency. An explanation of the experiment is given together with the necessary background, which provides the basis for a discussion of such operational considerations as upper frequency limit, sensitivity, temperature of operation, and saturation behavior at high signal levels. (Author)
Abstract Josephson devices have demonstrated the capability to work as harmonic mixers at terahertz frequencies. Low temperature devices, in particular Nb–Nb point contacts have proven particularly successful. However, practical applications of these devices have been limited by the need of utilizing liquid helium. To overcome this limitation we have investigated the use of high- T c devices. In this paper, we report mixings up to the 154th harmonic at zero-bias in a series of YBa 2 Cu 3 O 7−δ (YBCO) grain boundary Josephson junctions. We have integrated a meander series of three bicrystal YBCO Josephson junctions with a log-periodic antenna. When properly operated, this configuration allows to reach a harmonic number much higher than what possible with a single junction. This shows that the mixing performance benefits from the synchronous operation which also results in an improvement of dynamic range. We believe that the integration of a higher number of phase-locked junctions may further improve the mixer’s performance. Future studies should investigate the effect of higher number of junctions on the mixer performances, as well as the effect of the meander length.
We report heterodyne measurements of Josephson microwave radiation emitted by a parallel array of small superconductor-insulator-superconductor (SIS) junctions at submillimeter-wave frequencies. The array consists of five Nb/Al–AlOx/Nb junctions nonevenly distributed in a niobium superconducting stripline, and is optimized for rf coupling in the 450–640 GHz range. We observed Fiske-like resonant steps in its I-V curve in the presence of magnetic field. The device was placed in a waveguide mount, and its radiation was quasioptically coupled out of the cryostat, to a SIS-mixer spectrometer in the same frequency range, with a 4–8 GHz band for spectral analysis. We detected a coherent signal in the spectra when the array was biased on the first and third steps, respectively, at the first harmonic frequency of 242 GHz and at the fundamental frequency of 493 GHz, both being the Josephson frequencies associated with their dc voltages. This strongly suggests that this type of parallel arrays optimized for wideband rf coupling, though strongly discretized, hosts dynamic fluxon regimes similar to long Josephson junctions, which could find applications in superconducting digital electronics or integrated heterodyne submillimeter-wave receivers.
A weak link between two bulk superconductors can exhibit Josephson effects and can be used as a fast sensitive detector or mixer for electromagnetic radiation. Emphasis is placed on the millimeter and submillimeter range where such applications are potentially most important, though such devices should also work well at lower frequencies. The peculiar properties of the weak link make possible a variety of modes of operation including one in which it is both local oscillator and mixer. These modes of operation are analyzed and the pivotal experiments are reviewed. Noise and impedance matching are considered and comparison is made with other types of detectors of millimeter and submillimeter waves.