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 Magnetics

Self-radiation phenomena in LTSC and HTSC bridges

L. É. Amatuni, K. Y. Constantinian, R.B. Hayrapetian, G. A. Ovsyannikov, V. N. Laptev, V. I. Makhov

Published Mar 1, 1991• 3 citations
Publisher

Abstract

The nonlinear properties of Nb-Si-Nb high-quality edge-junctions and Y-Ba-Cu-O thin-film bridges were examined at several frequencies: f approximately=1.7, 21, and 39 GHz at T=4.2 K by means of the highly sensitive radiometric probe method. The results of self-pumping mixing regime in a single edge-junction and phase-locking processes in an array of 21 junctions are presented. The HTSC (high-temperature superconducting) bridge has exhibited strong generation intensity, more than 300 times higher than single edge-junctions, and stimulation of self-radiation under external microwave affection.

DOI
10.1109/20.133775

Related papers

Microwave mixing and generation in the low-Tcand high-Tcsuperconducting thin-film bridges

L. É. Amatuni, K. Y. Constantinian, A.A. Hakhumian +4 more

Microwave self-radiation at various frequencies and for different mixing processes in high quality Josephson edge-junctions based on Nb, and in thin-film bridges, based on Y-Ba-Cu-O have been experimentally studied and compared. High-T c samples were prepared using the surface-diffusion process on the insulating ceramic substrates. For the first time the authors describe the observation of a down-converted K-band noise signal obtained in a self-pumping mode.

Superconductor Science and Technology•Feb 1, 1992•3 citations

Detection of the Josephson self-radiation from YBCO step-edge junctions in millimeter-wave

K. Lee, Ienari Iguchi

We have investigated both DC and AC Josephson effects of the YBa/sub 2/Cu/sub 3/O/sub y/ (YBCO) thin film step-edge junctions; single step-edge junction on LaAlO/sub 3/ substrate with the step angle about 50-60/spl deg/ and biepitaxial double step-edge junction made on MgO substrate with a CeO/sub 2/ seed layer. The Josephson self-radiation was directly detected using the total power radiometer receiver systems with receiving frequencies of K band (21-23 GHz) and millimeter-wave (46-48 GHz and 71-73 GHz) range, respectively. For single step-edge junctions, the Josephson self-radiation peaks exhibited at the voltages corresponding to the basic Josephson voltage-frequency relation. The maximum first-harmonic self-radiation power at receiving frequency f/sub REC/=72 GHz and Josephson linewidth were P(I)=2.0/spl times/10/sup -3/W and /spl Delta/f=3.62 GHz at 4.2 K, respectively. For microwave irradiation, the harmonic Shapiro steps and additional half integer steps with their quasi-periodic variation satisfying the Josephson equation V=(n/m)(hf/2e) were clearly observed. For double step-edge junctions, we also observed the steps corresponding to the two junction boundaries on the two steep steps. These behaviors described with different current-phase relations corresponding to the crystal orientation relationship between the two junction boundaries.>

IEEE Transactions on Applied Superconductivity•Jun 1, 1995•2 citations

Microwave coupling of frequency-locked Josephson junction arrays

Insang Song, Yongheum Eom, Gwangseo Park +2 more

A high temperature superconducting YBa2Cu3Oy array of five Josephson junctions designed with additional coupling lines has been developed to demonstrate the effects of frequency locking and impedance matching for applications such as oscillators, mixers, and detectors. The Josephson self-radiation power was directly detected by a superheterodyne receiver, and Shapiro steps were also measured. The Josephson self-radiation properties reveal good quality of phase locking and microwave coupling with external circuits. The maximum self-radiation power of our array is about 50 pW which is several ten times higher than that of a single Josephson junction, and its peak point exactly satisfies the Josephson current-voltage relation. The Shapiro-step measurements show that the behavior of current-voltage curve depends on the effective inductance of coupling lines which affects the total impedance of Josephson junction array and microwave coupling. The Josephson oscillation frequency was obtained up to about 880 GHz which is 73% of the maximum available frequency calculated from the characteristic voltage of the Josephson junctions. Experimental results show that this type of Josephson junction array can improve the Josephson self-radiation power and increase the maximum detectable frequency.

Applied Physics Letters•Jun 16, 1997•8 citations

Spectral properties of rf emission from high T c films

Grzegorz Jung, Janusz Konopka, Stefano Vitale

Spectral properties of rf radiation from intrinsic Josephson junctions in high Tc Y-Ba-Cu-O thin film have been measured in the frequency range up to 1.5 GHz. Narrow emission lines with the 3 dB bandwidth of the order of 20 MHz were detected indicating that Josephson clusters radiate coherently. Synchronization conditions are determined by dc current and external magnetic field bias. Frequency locking of radiation to external resonant circuit was also observed. Spectral line narrowing due to resonant lock was distinguished from the coherence-induced narrowing by different tuning properties of the emission line. Noncoherent Josephson radiation manifests itself as a broadband background noise increase. A pronounced 1/f-like tail sensitive to dc bias and magnetic field was observed in a low frequency part of the spectrum.

Journal of Applied Physics•Sep 15, 1990•8 citations

Analysis of Josephson radiation from YBa2Cu3O7thin-film Josephson junctions

Gerhard Kunkel, M Bode, F Wang +4 more

We have investigated the Josephson radiation from different types of YBa 2 Cu 3 O 7 (YBCO) thin-film Josephson junctions: step-edge junctions (SEJs), biepitaxial junctions and SNS junctions with N=Au. The radiation was detected using a non-resonant radiometer system with a receiving frequency of 11-12 GHz. The current-voltage characteristics were measured simultaneously with the radiation spectra in the temperature range 4.2-90 K. All junctions exhibited a large emission peak at a voltage which was related to the frequency through the second Josephson relation. Typically, for high temperatures, and therefore small critical currents, the measured radiation linewidth agreed well with the theoretical predictions. At lower temperatures the experimental linewidths deviated from the theoretical values due to additional noise sources in the junctions. Some of the SEJs showed a non-monotonic dependence of the linewidth on temperature. It is suggested that such SEJ data may be discussed in terms of a model which treats the SEJ as an interferometer consisting of a parallel array of random Josephson junctions.

Superconductor Science and Technology•May 1, 1994•6 citations

Comparison of Josephson radiation properties of different YBa 2 Cu 3 O 7 thin film junctions

Gerhard Kunkel, M. Bode, F. Wang +6 more

We have investigated the Josephson radiation from different types of YBa2Cu3O7 (YBCO) thin film junctions: step-edge (SEJ), biepitaxial, and superconductor-normal conductor- superconductor (SNS) with N=Au and PrBa2Cu3O7. The radiation was detected using a nonresonant radiometer system with a receiving frequency of 11-12 GHz. The current-voltage characteristics were measured simultaneously with the radiation spectra in the temperature range from 4.2 to 90 K. All junctions exhibited a large emission peak at a voltage which was related to the frequency through the second Josephson relation. Typically, for high temperatures, and, therefore, small critical currents, the experimental data of the radiation linewidth agreed well with the theoretical predictions of the RSJ model. At lower temperatures the experimental linewidths deviated from the theoretical values due to additional noise sources in the junctions. Some of the SEJs showed a nonmonotonic dependence of the linewidth on temperature. Such SEJ data will be discussed in terms of a model which treats the SEJ as an interferometer consisting of a parallel array of Josephson junctions.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Jul 2, 1994•0 citations
The nonlinear properties of Nb-Si-Nb high-quality edge-junctions and Y-Ba-Cu-O thin-film bridges were examined at several frequencies: f approximately=1.7, 21, and 39 GHz at T=4.2 K by means of the highly sensitive radiometric probe method. The results of self-pumping mixing regime in a single edge-junction and phase-locking processes in an array of 21 junctions are presented. The HTSC (high-temperature superconducting) bridge has exhibited strong generation intensity, more than 300 times higher than single edge-junctions, and stimulation of self-radiation under external microwave affection.
We have investigated both DC and AC Josephson effects of the YBa/sub 2/Cu/sub 3/O/sub y/ (YBCO) thin film step-edge junctions; single step-edge junction on LaAlO/sub 3/ substrate with the step angle about 50-60/spl deg/ and biepitaxial double step-edge junction made on MgO substrate with a CeO/sub 2/ seed layer. The Josephson self-radiation was directly detected using the total power radiometer receiver systems with receiving frequencies of K band (21-23 GHz) and millimeter-wave (46-48 GHz and 71-73 GHz) range, respectively. For single step-edge junctions, the Josephson self-radiation peaks exhibited at the voltages corresponding to the basic Josephson voltage-frequency relation. The maximum first-harmonic self-radiation power at receiving frequency f/sub REC/=72 GHz and Josephson linewidth were P(I)=2.0/spl times/10/sup -3/W and /spl Delta/f=3.62 GHz at 4.2 K, respectively. For microwave irradiation, the harmonic Shapiro steps and additional half integer steps with their quasi-periodic variation satisfying the Josephson equation V=(n/m)(hf/2e) were clearly observed. For double step-edge junctions, we also observed the steps corresponding to the two junction boundaries on the two steep steps. These behaviors described with different current-phase relations corresponding to the crystal orientation relationship between the two junction boundaries.>
A high temperature superconducting YBa2Cu3Oy array of five Josephson junctions designed with additional coupling lines has been developed to demonstrate the effects of frequency locking and impedance matching for applications such as oscillators, mixers, and detectors. The Josephson self-radiation power was directly detected by a superheterodyne receiver, and Shapiro steps were also measured. The Josephson self-radiation properties reveal good quality of phase locking and microwave coupling with external circuits. The maximum self-radiation power of our array is about 50 pW which is several ten times higher than that of a single Josephson junction, and its peak point exactly satisfies the Josephson current-voltage relation. The Shapiro-step measurements show that the behavior of current-voltage curve depends on the effective inductance of coupling lines which affects the total impedance of Josephson junction array and microwave coupling. The Josephson oscillation frequency was obtained up to about 880 GHz which is 73% of the maximum available frequency calculated from the characteristic voltage of the Josephson junctions. Experimental results show that this type of Josephson junction array can improve the Josephson self-radiation power and increase the maximum detectable frequency.
Spectral properties of rf radiation from intrinsic Josephson junctions in high Tc Y-Ba-Cu-O thin film have been measured in the frequency range up to 1.5 GHz. Narrow emission lines with the 3 dB bandwidth of the order of 20 MHz were detected indicating that Josephson clusters radiate coherently. Synchronization conditions are determined by dc current and external magnetic field bias. Frequency locking of radiation to external resonant circuit was also observed. Spectral line narrowing due to resonant lock was distinguished from the coherence-induced narrowing by different tuning properties of the emission line. Noncoherent Josephson radiation manifests itself as a broadband background noise increase. A pronounced 1/f-like tail sensitive to dc bias and magnetic field was observed in a low frequency part of the spectrum.
We have investigated the Josephson radiation from different types of YBa 2 Cu 3 O 7 (YBCO) thin-film Josephson junctions: step-edge junctions (SEJs), biepitaxial junctions and SNS junctions with N=Au. The radiation was detected using a non-resonant radiometer system with a receiving frequency of 11-12 GHz. The current-voltage characteristics were measured simultaneously with the radiation spectra in the temperature range 4.2-90 K. All junctions exhibited a large emission peak at a voltage which was related to the frequency through the second Josephson relation. Typically, for high temperatures, and therefore small critical currents, the measured radiation linewidth agreed well with the theoretical predictions. At lower temperatures the experimental linewidths deviated from the theoretical values due to additional noise sources in the junctions. Some of the SEJs showed a non-monotonic dependence of the linewidth on temperature. It is suggested that such SEJ data may be discussed in terms of a model which treats the SEJ as an interferometer consisting of a parallel array of random Josephson junctions.
We have investigated the Josephson radiation from different types of YBa2Cu3O7 (YBCO) thin film junctions: step-edge (SEJ), biepitaxial, and superconductor-normal conductor- superconductor (SNS) with N=Au and PrBa2Cu3O7. The radiation was detected using a nonresonant radiometer system with a receiving frequency of 11-12 GHz. The current-voltage characteristics were measured simultaneously with the radiation spectra in the temperature range from 4.2 to 90 K. All junctions exhibited a large emission peak at a voltage which was related to the frequency through the second Josephson relation. Typically, for high temperatures, and, therefore, small critical currents, the experimental data of the radiation linewidth agreed well with the theoretical predictions of the RSJ model. At lower temperatures the experimental linewidths deviated from the theoretical values due to additional noise sources in the junctions. Some of the SEJs showed a nonmonotonic dependence of the linewidth on temperature. Such SEJ data will be discussed in terms of a model which treats the SEJ as an interferometer consisting of a parallel array of Josephson junctions.