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

YBCO microwave grain boundary mixer using a SrTiO/sub 3/ bicrystal substrate

R. Seed, Paul C. Dorsey, Hoton How, A. Widom, C. Vittoria

Published Nov 1, 1993• 4 citations
Publisher

Abstract

A microwave mixer was patterned on a microstrip transmission line of superconducting YBCO (YBa/sub 2/Cu/sub 3/O/sub 7-x/). The YBCO film was epitaxially laser deposited on a SrTiO/sub 3/ bicrystal substrate. A weak link was constructed by patterning a microbridge in the microstrip at the bicrystal boundary. Microwave signals at 9.000 GHz and 9.941 GHz were applied at the input of the microstrip line. An output intermediate frequency signal was observed at 941 MHz and was detected as the transmitted signal. The microbridge junction, which behaved as a resistively shunted Josephson junction (RSJ), was current biased slightly above the critical current I/sub c/. The mixer conversion loss was measured at the input and output ports of the device package. The mixing efficiency was determined at the device junction. This efficiency was compared with the calculated efficiency determined by numerical solution of the Josephson equation for the weak link junction.>

DOI
10.1109/20.281232

Related papers

Planar superconducting YBCO microwave mixer employing an engineered grain boundary weak link junction

R. Seed, Paul C. Dorsey, Hoton How +2 more

A microstrip transmission line was patterned from a superconducting YBa/sub 2/Cu/sub 3/O/sub 7-x/ film which was laser deposited on a SrTiO/sub 3/ bicrystal substrate. A microbridge in the microstrip was then patterned at the bicrystal interface to fabricate a superconducting grain boundary junction. Microwave mixing was observed with an input local oscillator frequency of 9.000 GHz, and an input signal frequency of 9.941 GHz. The output signal at 941 MHz was detected as a transmitted signal. The junction was current biased slightly above the critical current I/sub c/. The measured conversion loss was compared to the calculated value based upon a numerical solution of the equation for a superconducting weak link junction.>

IEEE Transactions on Applied Superconductivity•Jan 1, 1994•6 citations

Conversion gain and noise of YBa/sub 2/Cu/sub 3/O/sub 7/ weak-link mixers

Donald P. Butler, Jiaqi Wang, Anil Bhandari +1 more

Microwave mixing and parametric conversion in YBa/sub 2/Cu/sub 3/O/sub 7/ microbridges were investigated. The devices have been operated as down-converters, converting a 20-GHz radio frequency to a 1.5-GHz intermediate frequency under the action of an 18.5-GHz local oscillator. The microbridges were fabricated both as granular films on MgO substrates possessing grain boundary weak links and as epitaxial films deposited over substrate steps in LaAlO/sub 3/ substrates. The authors have measured conversion gains as high as -8+or-4 dB when mixing on the nonlinear resistive (superconducting-normal) transition and as high as -30 to -40 dB when parametrically converting via the nonlinear inductance of the bridge at bias currents less than the critical current. Output referred noise powers as low as -206 dB/Hz (3*10/sup -21/ W/Hz) have been measured. In some samples, noise switching events were observed.>

IEEE Transactions on Applied Superconductivity•Mar 1, 1993•5 citations

Millimeter-wave detection by GBJJ using high-T/sub c/ superconducting YBaCuO films

S. Kita, H. Tanabe, Takeshi Kobayashi

Millimeter-wave detection in the heterodyne mixing mode has been carried out using the high-T/sub c/ superconducting GBJJ (grain boundary Josephson junction). The GBJJ was fabricated from high T/sub c/ superconducting Y-Ba-Cu-O films, prepared on YSZ and SrTiO/sub 3/ substrates using an RF sputtering technique. The junction was patterned by chemical wet etching with phosphoric acid solution. The authors carried out experiments in the heterodyne mixing mode for a signal of 35 GHz with local oscillation at 34.97 GHz. The detected IF (intermediate frequency) output power was obtained at a bias voltage lying midway between the zeroth and first Shapiro steps. A mixer conversion efficiency of -15 dB was obtained with a dynamic range of about 20 dB at 35 GHz. This result strongly implies that high-T/sub c/ superconducting GBJJ works well as a detector at millimeter-wave frequencies.>

IEEE Transactions on Magnetics•Mar 1, 1989•16 citations

Millimeter Wave Mixing Properties of EuBa 2Cu 3O 7-δ Bicrystal Grain Boundary Junction Arrays

Koji Tsuru, Kazunori Miyahara, Minoru Suzuki

We report the millimeter wave mixing properties of high-T c superconductor Josephson junction arrays using a waveguide-to-microstrip converter in the 100 GHz frequency range. The junction arrays consist of 3 weak links fabricated from EuBa2Cu3O7-δ thin films grown on an MgO bicrystal substrate. In these junction arrays, Shapiro steps are observed in the presence of 100 GHz irradiation at intervals of 3 times the fundamental step voltage. Millimeter wave mixing with an input local oscillator frequency of 99.142 GHz and an input signal frequency of 99.880 GHz is detected as the IF output at 738 MHz. The IF output power peaks at voltages corresponding to those of the dynamic resistance dV/ dI. A mixing conversion efficiency of -24.1 dB is obtained for a 3-junction array.

Japanese Journal of Applied Physics•Dec 1, 1996•1 citation

High-temperature superconducting Josephson mixers from deliberate grain boundaries in Tl2CaBa2Cu2O8

Lincoln C. Bourne, Albert Humirang Cardona, Tim W. James +6 more

Deliberate grain boundaries have been fabricated in epitaxial films of Tl2CaBa2Cu2O8 by growing the films on substrates with localized surface damage and on substrates with surface steps produced with an anisotropic etching process. Bowtie antennas were fabricated to couple millimeter wave radiation into the weak link junctions, which were used as the nonlinear elements. Heterodyne mixing of signals at 55 GHz and 94 GHz was observed in the integrated antenna/detector structures at temperatures below 101 K in the Tl-based films. In addition, observations were made at 55 GHz, using these structures as subharmonic mixers. We have designed an integrated microwave package to measure the noise and conversion efficiency of the grain-boundary junctions at frequencies between 9 GHz and 20 GHz.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Jul 1, 1991•2 citations

Microwave Heterodyne Mixing by Step-Edge Microbridge Josephson Junctions Using YBaCuO Thin Films

Yoshito Fukumoto, Hiroshi Kajikawa, Rikuo Ogawa +1 more

Current-voltage characteristics and microwave mixing properties of step-edge microbridge Josephson junctions (SEJJs) made of YBaCuO thin films were systematically investigated. The step-edge was formed on the surface of a MgO(100) substrate employing the common photolithograph and wet-etching techniques. YBaCuO thin film was deposited by the off-axis sputtering method, and the microbridge junctions were fabricated so as to cross the step-edge. The SEJJs showed typical DC and AC characteristics which were explained by the resistively shunted junction (RSJ) model. Mixing experiments were carried out in the K-band microwave region. An intermediate frequency (IF) output with the frequency range of 20 MHz~2.0 GHz was successfully obtained.

International Conference on Solid State Devices and Materials (SSDM)•Aug 28, 1991•0 citations
A microwave mixer was patterned on a microstrip transmission line of superconducting YBCO (YBa/sub 2/Cu/sub 3/O/sub 7-x/). The YBCO film was epitaxially laser deposited on a SrTiO/sub 3/ bicrystal substrate. A weak link was constructed by patterning a microbridge in the microstrip at the bicrystal boundary. Microwave signals at 9.000 GHz and 9.941 GHz were applied at the input of the microstrip line. An output intermediate frequency signal was observed at 941 MHz and was detected as the transmitted signal. The microbridge junction, which behaved as a resistively shunted Josephson junction (RSJ), was current biased slightly above the critical current I/sub c/. The mixer conversion loss was measured at the input and output ports of the device package. The mixing efficiency was determined at the device junction. This efficiency was compared with the calculated efficiency determined by numerical solution of the Josephson equation for the weak link junction.>
A microstrip transmission line was patterned from a superconducting YBa/sub 2/Cu/sub 3/O/sub 7-x/ film which was laser deposited on a SrTiO/sub 3/ bicrystal substrate. A microbridge in the microstrip was then patterned at the bicrystal interface to fabricate a superconducting grain boundary junction. Microwave mixing was observed with an input local oscillator frequency of 9.000 GHz, and an input signal frequency of 9.941 GHz. The output signal at 941 MHz was detected as a transmitted signal. The junction was current biased slightly above the critical current I/sub c/. The measured conversion loss was compared to the calculated value based upon a numerical solution of the equation for a superconducting weak link junction.>
Microwave mixing and parametric conversion in YBa/sub 2/Cu/sub 3/O/sub 7/ microbridges were investigated. The devices have been operated as down-converters, converting a 20-GHz radio frequency to a 1.5-GHz intermediate frequency under the action of an 18.5-GHz local oscillator. The microbridges were fabricated both as granular films on MgO substrates possessing grain boundary weak links and as epitaxial films deposited over substrate steps in LaAlO/sub 3/ substrates. The authors have measured conversion gains as high as -8+or-4 dB when mixing on the nonlinear resistive (superconducting-normal) transition and as high as -30 to -40 dB when parametrically converting via the nonlinear inductance of the bridge at bias currents less than the critical current. Output referred noise powers as low as -206 dB/Hz (3*10/sup -21/ W/Hz) have been measured. In some samples, noise switching events were observed.>
Millimeter-wave detection in the heterodyne mixing mode has been carried out using the high-T/sub c/ superconducting GBJJ (grain boundary Josephson junction). The GBJJ was fabricated from high T/sub c/ superconducting Y-Ba-Cu-O films, prepared on YSZ and SrTiO/sub 3/ substrates using an RF sputtering technique. The junction was patterned by chemical wet etching with phosphoric acid solution. The authors carried out experiments in the heterodyne mixing mode for a signal of 35 GHz with local oscillation at 34.97 GHz. The detected IF (intermediate frequency) output power was obtained at a bias voltage lying midway between the zeroth and first Shapiro steps. A mixer conversion efficiency of -15 dB was obtained with a dynamic range of about 20 dB at 35 GHz. This result strongly implies that high-T/sub c/ superconducting GBJJ works well as a detector at millimeter-wave frequencies.>
We report the millimeter wave mixing properties of high-T c superconductor Josephson junction arrays using a waveguide-to-microstrip converter in the 100 GHz frequency range. The junction arrays consist of 3 weak links fabricated from EuBa2Cu3O7-δ thin films grown on an MgO bicrystal substrate. In these junction arrays, Shapiro steps are observed in the presence of 100 GHz irradiation at intervals of 3 times the fundamental step voltage. Millimeter wave mixing with an input local oscillator frequency of 99.142 GHz and an input signal frequency of 99.880 GHz is detected as the IF output at 738 MHz. The IF output power peaks at voltages corresponding to those of the dynamic resistance dV/ dI. A mixing conversion efficiency of -24.1 dB is obtained for a 3-junction array.
Deliberate grain boundaries have been fabricated in epitaxial films of Tl2CaBa2Cu2O8 by growing the films on substrates with localized surface damage and on substrates with surface steps produced with an anisotropic etching process. Bowtie antennas were fabricated to couple millimeter wave radiation into the weak link junctions, which were used as the nonlinear elements. Heterodyne mixing of signals at 55 GHz and 94 GHz was observed in the integrated antenna/detector structures at temperatures below 101 K in the Tl-based films. In addition, observations were made at 55 GHz, using these structures as subharmonic mixers. We have designed an integrated microwave package to measure the noise and conversion efficiency of the grain-boundary junctions at frequencies between 9 GHz and 20 GHz.
Current-voltage characteristics and microwave mixing properties of step-edge microbridge Josephson junctions (SEJJs) made of YBaCuO thin films were systematically investigated. The step-edge was formed on the surface of a MgO(100) substrate employing the common photolithograph and wet-etching techniques. YBaCuO thin film was deposited by the off-axis sputtering method, and the microbridge junctions were fabricated so as to cross the step-edge. The SEJJs showed typical DC and AC characteristics which were explained by the resistively shunted junction (RSJ) model. Mixing experiments were carried out in the K-band microwave region. An intermediate frequency (IF) output with the frequency range of 20 MHz~2.0 GHz was successfully obtained.