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

International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz)

Noise figure measurement of high temperature superconducting bi-crystal josephson junction THz mixers

Deyue An, Weiwei Xu, Tao Hua, D. C. Li, M. Yu, J. Chen, Peiheng Wu

Published Sep 1, 2012• 1 citation
Publisher

Abstract

Using the Y-factor measurement method, we estimated the noise figure (NF) of the high temperature superconducting bi-crystal Josephson junction mixer. The experiment was based on small pulse tube refrigerator, working at 60 K. We tested and analysed the dependence of bias voltage and local oscillation signal power with the noise figure.
DOI
10.1109/irmmw-thz.2012.6380129

Related papers

NOISE FIGURE MEASUREMENT OF HIGH TEMPERATURE SUPERCONDUCTING Bi-CRYSTAL JOSEPHSON JUNCTION MIXERS

Peiheng Wu

Noise figure(NF) is an important parameter of the superconducting mixer,which is a key indicator of the mixer's sensitivity depending on the internal noise.Using the efficient and durable small size pulse tube refrigerator for the cold source,we designed the High Temperature Superconducting(HTS) Josephson junction harmonic mixer and noise figure automatic measurement systems which operated at 60 K.YBa2Cu3O7-δ(YBCO)/MgO Josephson junctions was fabricated through argon ion band etching.Using the Y-factor measurement method,we estimated the noise figure of the HTS Josephson junction mixer with conventional hot/cold blackbodies irradiation techniques.The Josephson junction,we had successfully fabricated,had 1mV characteristic voltage,and it had good microwave response and high harmonic numbers at operating frequencies around 650 GHz.At the 30th harmonic of fS=210GHz,the double-crystal Josephson junction biased in the different voltages,IF output signal to noise ratio changed in the range of 30 dB.The noise figure had a minimum 10 dB at a bias voltage of 300 μV and at the irradiation of blackbodies at 77 K and 300 K.

•Jan 1, 2012•0 citations

Noise and conversion performance of a high-Tc superconducting Josephson junction mixer at 0.6 THz

Xiang Gao, Jia Du, Ting Zhang +1 more

This letter presents both theoretical and experimental investigations on the noise and conversion performance of a high-Tc superconducting (HTS) step-edge Josephson-junction mixer at the frequency of 0.6 THz and operating temperatures of 20–40 K. Based on the Y-factor and U-factor methods, a double-sideband noise temperature of around 1000 K and a conversion gain of −3.5 dB were experimentally obtained at 20 K. At the temperature of 40 K, the measured mixer noise and conversion efficiency are around 2100 K and −10 dB, respectively. The experimental data are in good agreement with the numerical analysis results using the three-port model. A detailed performance comparison with other reported HTS terahertz mixers has confirmed the superior performance of our presented mixer device.

Applied Physics Letters•Nov 6, 2017•25 citations

Noise and Conversion Analyses for High-T c Superconducting Harmonic Mixers: Theoretical Modeling and Experimental Verification

Huanxin Li, Xiang Gao, Jianping An +2 more

High-Tcsuperconducting (HTS) harmonic mixers are attractive frontends for terahertz wireless communication and sensing applications. However, the investigation of HTS harmonic mixers has long been hindered by the lack of effective theoretical method in device modeling. This article presents a modeling approach for analyzing the noise and conversion properties of HTS harmonic mixers. By quantitively analyzing the contribution of the parasitic components to frequency conversion, a parasitics-selection based equivalent circuit model is built with the architecture complexity reduced to a six-port network. Besides, a fast hybrid-solution method that combines the single-tone current excitation and perturbation-derivation processing techniques, is developed for efficiently calculating the conversion impedance matrix for harmonic mixing. Detailed derivations are then carried out to acquire the semianalytic expressions of noise temperature and conversion gain after solving the noise correlation matrix for harmonic mixing. The presented modeling method has been verified by the fourth harmonic mixing experiments for a dual-band antenna-coupled HTS Josephson-junction mixer module. The measured and simulated results are in good agreement in terms of the noise temperature and conversion gain as well as their dependance on dc biasing, local oscillator pumping, and operating temperatures. The results have validated the effectiveness of the presented modeling method for analyzing the properties of HTS Josephson junction mixers.

IEEE Transactions on Terahertz Science and Technology•Feb 24, 2022•5 citations

The Influence of LO Power Heating of the Tunnel Junction on the Performance of THz SIS Mixers

Alessandro Traini, Boon-Kok Tan, John Garrett +6 more

We describe the performance of a superconductor- insulator-superconductor (SIS) mixer operating in the frequency range of 780-950 GHz. Unlike most SIS mixers, the tunnel junction employs two different superconductors, a niobium nitride top and a niobium bottom electrode sandwiching an aluminum nitride barrier layer, fabricated on a niobium titanium nitride ground plane. The mixer was tested in a pulse tube cryostat, with all the optical components, in the signal path, mounted inside the vacuum environment to avoid attenuation of the RF signal as it propagates from the hot/cold loads to the mixer. With this setup, we have measured an RF-corrected noise temperature of ~220 K. In this article, we focus on investigating the influence of local oscillator (LO) power heating on the performance of the terahertz mixer. The increase in the junction's physical temperature can be observed experimentally by noting the suppression of the gap voltage in the pumped current-voltage (I-V ) curve as the LO pumping level is increased. Similar observation has already been reported, and attempts were made to estimate the effective temperature of the device using equations of heat transfer between the mixer chip layers. Here, we present an experimental method of quantifying this effect by recovering the effective temperature of the junction through comparing the pumped I-V curves at different pumping levels and fixed bath temperature, with the unpumped I-V curves obtained at varying bath temperatures. We also estimate, for the first time, the effect of heating on the noise temperature as a function of bath temperature and frequency. We show that for typical experimental parameters, the LO heating can increase the double-sideband receiver noise temperature by as much as 20%, and that in the frequency range of the measurements, the effective temperature of the junction at fixed LO power increases linearly with frequency at a rate of 0.5 K/100 GHz.

IEEE Transactions on Terahertz Science and Technology•Sep 30, 2020•5 citations

Noise and conversion properties of Y–Ba–Cu–O Josephson mixers at operating temperatures above 20 K

Oliver Harnack, Marian Darula, Stephan Beuven +1 more

We have measured the noise performance and conversion efficiency of Y–Ba–Cu–O bicrystal Josephson mixers at operating temperatures between 20 and 60 K and at operating frequencies around 90 GHz. A double-sideband mixer noise temperature of about 1600 K and a conversion efficiency of −10 dB at 20 K operating temperature has been measured using the Y-factor method. The absorbed local oscillator power was in the range of 10 nW. The dependence of the mixer performance on the normalized frequency Ω and the fluctuation parameter Γ has been studied. In accordance with the resistively shunted junction model, the experimental data show the presence of excess noise. The temperature dependence of the mixer noise temperature can be explained by the variation of the linewidth of the Josephson oscillations with the operating temperature.

Applied Physics Letters•Mar 27, 2000•12 citations

Shot noise in YBCO bicrystal Josephson junctions

K. Y. Constantinian, G. A. Ovsyannikov, I. V. Borisenko +2 more

We measured spectral noise density in YBCO symmetric bicrystal Josephson junctions on sapphire substrates at bias voltages up to 100 mV and T=4.2 K. Normal state resistance of the Josephson junctions, R/sub N/=20-90 /spl Omega/ and I/sub C/R/sub N/ up to 2.2 mV have been observed in the experimental samples. Noise measurements were carried out within frequency bands of 1-2 GHz and 0.3-300 kHz. At bias voltages 10/spl les/V/spl les/60 mV a linear voltage dependence of noise power has been registered, while at V/spl les/5 mV a noticeable noise rise has been observed. The latter may explain the experimentally measured linewidth broadening of Josephson oscillations at mm and submm wave frequencies in high-Tc superconducting junctions. Experimental results are discussed in terms of bound states existing at surfaces of d-wave superconducting electrodes.

IEEE Transactions on Applied Superconductivity•Jun 1, 2003•5 citations
Noise figure(NF) is an important parameter of the superconducting mixer,which is a key indicator of the mixer's sensitivity depending on the internal noise.Using the efficient and durable small size pulse tube refrigerator for the cold source,we designed the High Temperature Superconducting(HTS) Josephson junction harmonic mixer and noise figure automatic measurement systems which operated at 60 K.YBa2Cu3O7-δ(YBCO)/MgO Josephson junctions was fabricated through argon ion band etching.Using the Y-factor measurement method,we estimated the noise figure of the HTS Josephson junction mixer with conventional hot/cold blackbodies irradiation techniques.The Josephson junction,we had successfully fabricated,had 1mV characteristic voltage,and it had good microwave response and high harmonic numbers at operating frequencies around 650 GHz.At the 30th harmonic of fS=210GHz,the double-crystal Josephson junction biased in the different voltages,IF output signal to noise ratio changed in the range of 30 dB.The noise figure had a minimum 10 dB at a bias voltage of 300 μV and at the irradiation of blackbodies at 77 K and 300 K.
This letter presents both theoretical and experimental investigations on the noise and conversion performance of a high-Tc superconducting (HTS) step-edge Josephson-junction mixer at the frequency of 0.6 THz and operating temperatures of 20–40 K. Based on the Y-factor and U-factor methods, a double-sideband noise temperature of around 1000 K and a conversion gain of −3.5 dB were experimentally obtained at 20 K. At the temperature of 40 K, the measured mixer noise and conversion efficiency are around 2100 K and −10 dB, respectively. The experimental data are in good agreement with the numerical analysis results using the three-port model. A detailed performance comparison with other reported HTS terahertz mixers has confirmed the superior performance of our presented mixer device.
High-Tcsuperconducting (HTS) harmonic mixers are attractive frontends for terahertz wireless communication and sensing applications. However, the investigation of HTS harmonic mixers has long been hindered by the lack of effective theoretical method in device modeling. This article presents a modeling approach for analyzing the noise and conversion properties of HTS harmonic mixers. By quantitively analyzing the contribution of the parasitic components to frequency conversion, a parasitics-selection based equivalent circuit model is built with the architecture complexity reduced to a six-port network. Besides, a fast hybrid-solution method that combines the single-tone current excitation and perturbation-derivation processing techniques, is developed for efficiently calculating the conversion impedance matrix for harmonic mixing. Detailed derivations are then carried out to acquire the semianalytic expressions of noise temperature and conversion gain after solving the noise correlation matrix for harmonic mixing. The presented modeling method has been verified by the fourth harmonic mixing experiments for a dual-band antenna-coupled HTS Josephson-junction mixer module. The measured and simulated results are in good agreement in terms of the noise temperature and conversion gain as well as their dependance on dc biasing, local oscillator pumping, and operating temperatures. The results have validated the effectiveness of the presented modeling method for analyzing the properties of HTS Josephson junction mixers.
We describe the performance of a superconductor- insulator-superconductor (SIS) mixer operating in the frequency range of 780-950 GHz. Unlike most SIS mixers, the tunnel junction employs two different superconductors, a niobium nitride top and a niobium bottom electrode sandwiching an aluminum nitride barrier layer, fabricated on a niobium titanium nitride ground plane. The mixer was tested in a pulse tube cryostat, with all the optical components, in the signal path, mounted inside the vacuum environment to avoid attenuation of the RF signal as it propagates from the hot/cold loads to the mixer. With this setup, we have measured an RF-corrected noise temperature of ~220 K. In this article, we focus on investigating the influence of local oscillator (LO) power heating on the performance of the terahertz mixer. The increase in the junction's physical temperature can be observed experimentally by noting the suppression of the gap voltage in the pumped current-voltage (I-V ) curve as the LO pumping level is increased. Similar observation has already been reported, and attempts were made to estimate the effective temperature of the device using equations of heat transfer between the mixer chip layers. Here, we present an experimental method of quantifying this effect by recovering the effective temperature of the junction through comparing the pumped I-V curves at different pumping levels and fixed bath temperature, with the unpumped I-V curves obtained at varying bath temperatures. We also estimate, for the first time, the effect of heating on the noise temperature as a function of bath temperature and frequency. We show that for typical experimental parameters, the LO heating can increase the double-sideband receiver noise temperature by as much as 20%, and that in the frequency range of the measurements, the effective temperature of the junction at fixed LO power increases linearly with frequency at a rate of 0.5 K/100 GHz.
We have measured the noise performance and conversion efficiency of Y–Ba–Cu–O bicrystal Josephson mixers at operating temperatures between 20 and 60 K and at operating frequencies around 90 GHz. A double-sideband mixer noise temperature of about 1600 K and a conversion efficiency of −10 dB at 20 K operating temperature has been measured using the Y-factor method. The absorbed local oscillator power was in the range of 10 nW. The dependence of the mixer performance on the normalized frequency Ω and the fluctuation parameter Γ has been studied. In accordance with the resistively shunted junction model, the experimental data show the presence of excess noise. The temperature dependence of the mixer noise temperature can be explained by the variation of the linewidth of the Josephson oscillations with the operating temperature.
We measured spectral noise density in YBCO symmetric bicrystal Josephson junctions on sapphire substrates at bias voltages up to 100 mV and T=4.2 K. Normal state resistance of the Josephson junctions, R/sub N/=20-90 /spl Omega/ and I/sub C/R/sub N/ up to 2.2 mV have been observed in the experimental samples. Noise measurements were carried out within frequency bands of 1-2 GHz and 0.3-300 kHz. At bias voltages 10/spl les/V/spl les/60 mV a linear voltage dependence of noise power has been registered, while at V/spl les/5 mV a noticeable noise rise has been observed. The latter may explain the experimentally measured linewidth broadening of Josephson oscillations at mm and submm wave frequencies in high-Tc superconducting junctions. Experimental results are discussed in terms of bound states existing at surfaces of d-wave superconducting electrodes.