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

Integrated High-T/sub c/ oscillator array and high resistance detector junction

J. Edstam, G. Brorsson, Е. А. Степанцов, H. Olsson

Published Jun 1, 1995• 8 citations
Publisher

Abstract

We have integrated an array of five High-T/sub c/ Josephson junction oscillators with a Josephson detector junction of high resistance, e.g. 25 /spl Omega/. High impedance detectors are suitable in integrated superconducting receivers. We find the output power to be sufficient to modulate the detector junction with large Shapiro steps in the frequency range 200-700 GHz. The oscillator junctions were dc-biased in parallel and integrated in an inductive high frequency coupling circuit to oscillate coherently in-phase. The high frequency coupling circuit is evaluated through its influence on the current-voltage characteristic of the Josephson junctions.>

DOI
10.1109/77.403291

Related papers

Microwave coupling of the Josephson junction arrays with an external source

Insang Song, Yunsung Huh, Gwangseo Park +4 more

We have fabricated a YBa/sub 2/Cu/sub 3/O/sub y/ (YBCO) array of five Josephson junctions designed with additional inductive coupling lines (AICLs). The junctions in this array were dc-biased in parallel to oscillate coherently in-phase and integrated with AICLs to improve the impedance matching between this array and external circuits such as a waveguide. The effect of AICLs was investigated by studying its influence on the current-voltage characteristics of the Josephson junction array (JJA) under external microwave irradiations with frequency of 22 GHz. The experimental results show that the behavior of the Shapiro-steps depends upon the effective inductance of AICLs which affects the total impedance and microwave coupling. We were able to obtain an oscillation frequency of about 73% of the maximum available frequency calculated from the characteristic voltage of the Josephson junctions in the array at a temperature of 12 K. By calculating the total impedance of the array, we obtained the suitable parameters of the array for microwave coupling with waveguide for various values of inductance, ac frequencies and number of Josephson junctions.

IEEE Transactions on Applied Superconductivity•Jun 1, 1997•7 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

Properties of Josephson array oscillators at the submillimeter wave region

Akira Kawakami, Yoshinori Uzawa, Z. Wang

We have developed resistively shunted tunnel junctions with a small parasitic inductance (/spl equiv/100 fH) to improve the high-frequency performance of Josephson array oscillators. Josephson array oscillators with 11 such junctions and Nb microstrip resonators were designed and fabricated to operate at 690 GHz. Shapiro steps induced by Josephson oscillation were clearly observed at the submillimeter frequency region. By comparing the step height with the numerical simulation, we estimated the power of the Josephson oscillator delivered to the load resistor to be about 10 /spl mu/W at 625 GHz. The linewidth of the Josephson array oscillator was also measured using an integrated receiver consisting of two Josephson array oscillators and an SIS mixer. The designed frequency of the receiver was set at 550 GHz. IF output power spectrum was observed when both the oscillators were biased at about 1.17 mV which corresponds to 566 GHz. The composite linewidth of Josephson oscillation was measured about 8 MHz at 4.2 K.

IEEE Transactions on Applied Superconductivity•Jun 1, 1999•12 citations

On-chip integration of HTS Josephson oscillator and mixer

S. Beuven, Marian Darula, Oliver Harnack +2 more

We report on the experimental realization of a sub-mm wavelength oscillator based on HTS Josephson junctions integrated on-chip with detector Josephson junction-mixer. Detector and oscillator are coupled via a microstripline. The oscillator is a 2-dimensional (2D) network (array) of 20 HTS step-edge junctions. The array is biased in parallel, i.e. all junctions of the network are oscillating with the same frequency. Effective pumping of the Josephson mixer was possible up to several hundred GHz. The best results, i.e. significant depression of the critical current and steep Shapiro steps up to the 4th order, were obtained between 150 GHz and 200 GHz. Power transfer was detectable up to frequencies around 1.15 THz.

IEEE Transactions on Applied Superconductivity•Jun 1, 1999•2 citations

On and off-chip detection of radiation from HTS Josephson junction arrays

Kiejin Lee, Ienari Iguchi, K. Y. Constantinian

We have investigated the mutual phase interaction between a single detector junction and a phase-locked three-junction array of high-T/sub c/ Josephson junctions. The YBCO Josephson junctions were fabricated on a MgO bicrystal substrate. In the array junction structure, the dc bias current was fed to the junction array having parallel geometry with each pair of junctions shunted by a superconducting coplanar microstrip superconducting loop. The configuration of bias leads was a series connection of interlocking dc SQUIDs geometry which enables all junctions to oscillate at the same frequency. We measured the radiation power of a Josephson-junction array using an off-chip coupled to a radiometer and on-chip coupled to a single junction from centimeter- to millimeter-wave ranges. Clear self-induced Shapiro steps were observed in the current-voltage curves of the detector junction. The power transfered to the single detector junction was estimated from the modulation of Shapiro step height. The maximum detected power level was about 7 nW at frequency 150-250 GHz. The Josephson oscillation power excited the resonant mode coupled to the coplanar microstrip loops.

IEEE Transactions on Applied Superconductivity•Jun 1, 1999•1 citation

Hybrid integration of microwave oscillators with Josephson series arrays for the use as voltage standards

Franz X. Hebrank, P. Gutmann, F. Muller +2 more

We have designed and fabricated a new type of Josephson device to be hybrid integrated with microstripline oscillators. For optimum matching of the Josephson series array to the oscillator the samples make use of a new stripline design. The first circuits were fabricated in a simplified Nb/Al/sub 2/O/sub 3//Nb technology and exhibit excellent dc characteristics and good microwave coupling to the junctions of the array. At 70 GHz constant voltage steps up to 350 mV could be observed. By hybrid integrating different samples with a new 10-GHz oscillator, constant voltage steps were created. For this experiment the Josephson current density had to be low enough to reduce the plasma frequency of the junctions to well below the driving frequency.>

IEEE Transactions on Applied Superconductivity•Jun 1, 1995•5 citations
We have integrated an array of five High-T/sub c/ Josephson junction oscillators with a Josephson detector junction of high resistance, e.g. 25 /spl Omega/. High impedance detectors are suitable in integrated superconducting receivers. We find the output power to be sufficient to modulate the detector junction with large Shapiro steps in the frequency range 200-700 GHz. The oscillator junctions were dc-biased in parallel and integrated in an inductive high frequency coupling circuit to oscillate coherently in-phase. The high frequency coupling circuit is evaluated through its influence on the current-voltage characteristic of the Josephson junctions.>
We have fabricated a YBa/sub 2/Cu/sub 3/O/sub y/ (YBCO) array of five Josephson junctions designed with additional inductive coupling lines (AICLs). The junctions in this array were dc-biased in parallel to oscillate coherently in-phase and integrated with AICLs to improve the impedance matching between this array and external circuits such as a waveguide. The effect of AICLs was investigated by studying its influence on the current-voltage characteristics of the Josephson junction array (JJA) under external microwave irradiations with frequency of 22 GHz. The experimental results show that the behavior of the Shapiro-steps depends upon the effective inductance of AICLs which affects the total impedance and microwave coupling. We were able to obtain an oscillation frequency of about 73% of the maximum available frequency calculated from the characteristic voltage of the Josephson junctions in the array at a temperature of 12 K. By calculating the total impedance of the array, we obtained the suitable parameters of the array for microwave coupling with waveguide for various values of inductance, ac frequencies and number of Josephson junctions.
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.
We have developed resistively shunted tunnel junctions with a small parasitic inductance (/spl equiv/100 fH) to improve the high-frequency performance of Josephson array oscillators. Josephson array oscillators with 11 such junctions and Nb microstrip resonators were designed and fabricated to operate at 690 GHz. Shapiro steps induced by Josephson oscillation were clearly observed at the submillimeter frequency region. By comparing the step height with the numerical simulation, we estimated the power of the Josephson oscillator delivered to the load resistor to be about 10 /spl mu/W at 625 GHz. The linewidth of the Josephson array oscillator was also measured using an integrated receiver consisting of two Josephson array oscillators and an SIS mixer. The designed frequency of the receiver was set at 550 GHz. IF output power spectrum was observed when both the oscillators were biased at about 1.17 mV which corresponds to 566 GHz. The composite linewidth of Josephson oscillation was measured about 8 MHz at 4.2 K.
We report on the experimental realization of a sub-mm wavelength oscillator based on HTS Josephson junctions integrated on-chip with detector Josephson junction-mixer. Detector and oscillator are coupled via a microstripline. The oscillator is a 2-dimensional (2D) network (array) of 20 HTS step-edge junctions. The array is biased in parallel, i.e. all junctions of the network are oscillating with the same frequency. Effective pumping of the Josephson mixer was possible up to several hundred GHz. The best results, i.e. significant depression of the critical current and steep Shapiro steps up to the 4th order, were obtained between 150 GHz and 200 GHz. Power transfer was detectable up to frequencies around 1.15 THz.
We have investigated the mutual phase interaction between a single detector junction and a phase-locked three-junction array of high-T/sub c/ Josephson junctions. The YBCO Josephson junctions were fabricated on a MgO bicrystal substrate. In the array junction structure, the dc bias current was fed to the junction array having parallel geometry with each pair of junctions shunted by a superconducting coplanar microstrip superconducting loop. The configuration of bias leads was a series connection of interlocking dc SQUIDs geometry which enables all junctions to oscillate at the same frequency. We measured the radiation power of a Josephson-junction array using an off-chip coupled to a radiometer and on-chip coupled to a single junction from centimeter- to millimeter-wave ranges. Clear self-induced Shapiro steps were observed in the current-voltage curves of the detector junction. The power transfered to the single detector junction was estimated from the modulation of Shapiro step height. The maximum detected power level was about 7 nW at frequency 150-250 GHz. The Josephson oscillation power excited the resonant mode coupled to the coplanar microstrip loops.
We have designed and fabricated a new type of Josephson device to be hybrid integrated with microstripline oscillators. For optimum matching of the Josephson series array to the oscillator the samples make use of a new stripline design. The first circuits were fabricated in a simplified Nb/Al/sub 2/O/sub 3//Nb technology and exhibit excellent dc characteristics and good microwave coupling to the junctions of the array. At 70 GHz constant voltage steps up to 350 mV could be observed. By hybrid integrating different samples with a new 10-GHz oscillator, constant voltage steps were created. For this experiment the Josephson current density had to be low enough to reduce the plasma frequency of the junctions to well below the driving frequency.>