This paper describes an array of superconducting planar Josephson junctions (JJs) for terahertz emission. The JJs with bowtie antennae are fabricated with superconducting thin film deposited on the bicrystal dielectric substrate and connected in series by superconducting striplines. The dielectric substrate is regarded as a dielectric resonator to improve the electromagnetic coupling between the JJs for coherent terahertz emission. With the CST electromagnetic software, the S parameters, E-field distribution and farfield pattern of the JJ array are studied by adjusting the width of the bowtie antennae. The results show that standing waves are formed in the dielectric substrate around 420 GHz, which could contribute to the coherent terahertz emission of the superconducting oscillators.This paper describes an array of superconducting planar Josephson junctions (JJs) for terahertz emission. The JJs with bowtie antennae are fabricated with superconducting thin film deposited on the bicrystal dielectric substrate and connected in series by superconducting striplines. The dielectric substrate is regarded as a dielectric resonator to improve the electromagnetic coupling between the JJs for coherent terahertz emission. With the CST electromagnetic software, the S parameters, E-field distribution and farfield pattern of the JJ array are studied by adjusting the width of the bowtie antennae. The results show that standing waves are formed in the dielectric substrate around 420 GHz, which could contribute to the coherent terahertz emission of the superconducting oscillators.

CIE International Conference on Radar (RADAR)Oct 1, 20160 citations

A new 10-V array of Josephson junctions based on low-frequency designs scaled up to 94 GHz

Hiroyuki Yoshida, Y. Murayama, T. Endo

A novel approach is described for the design of improved coupling of millimeter-waves in a 10-V array of Josephson junctions. In this approach, microwave structures were fabricated and tested in the range 2.8 GHz to 3.6 GHz, and a scaling calculation was then used to transform them to 94 GHz. By optimizing the trade-off between antenna size and efficiency, it was possible to make more space available on the device chip to increase the number of Josephson junctions. Simulation results showed that the optimal antenna is a short double-fin-line type. This antenna type allowed us to fabricate a Josephson junction array that had 25944 Nb/Al-AlO/sub x//Nb junctions. For this new array, zero-crossing steps were observed up to 18.5 V. The new array was then successfully used to calibrate a Zener voltage standard that had a 10-V output.A novel approach is described for the design of improved coupling of millimeter-waves in a 10-V array of Josephson junctions. In this approach, microwave structures were fabricated and tested in the range 2.8 GHz to 3.6 GHz, and a scaling calculation was then used to transform them to 94 GHz. By optimizing the trade-off between antenna size and efficiency, it was possible to make more space available on the device chip to increase the number of Josephson junctions. Simulation results showed that the optimal antenna is a short double-fin-line type. This antenna type allowed us to fabricate a Josephson junction array that had 25944 Nb/Al-AlO/sub x//Nb junctions. For this new array, zero-crossing steps were observed up to 18.5 V. The new array was then successfully used to calibrate a Zener voltage standard that had a 10-V output.

IEEE Transactions on Instrumentation and MeasurementJan 1, 19974 citations

Wireless Josephson Junction Arrays

Laura Adams

Bulletin of the American Physical SocietyMar 3, 20150 citations

A 220-GHz Miniaturized Antenna-Coupled Mixer Based on $\mathbf{Bi}_{2} \mathbf{Sr}_{2} \mathbf{CaCu}_{2} \mathbf{O}_{8}$ Josephson Junction ArrayA 220-GHz Miniaturized Antenna-Coupled Mixer Based on $\mathbf{Bi}_{2} \mathbf{Sr}_{2} \mathbf{CaCu}_{2} \mathbf{O}_{8}$ Josephson Junction Array

Dan Qiao, Xiang Gao, Ziru Chen +4 more

This paper presents the design and simulation of a 220-GHz miniaturized slot-antenna-coupled high-temperature superconducting (HTS) mixer, which integrates the HTS junction and the choke filter on one single substrate. The presented mixer utilizes $\mathbf{Bi_{2}}\mathbf{Sr_{2}}\mathbf{CaCu}2\mathbf{O_{8}}$ (BSCCO) intrinsic Josephson junction array as the nonlinear mixing device. To compensate the parasitic capacitance of the BSCCO junction, a short transmission line is used as an inductance for improving impedance matching between the slot antenna and the BSCCO Josephson junction array. The simulation results show that the proposed mixer achieves a conversion gain and noise temperature of -6.74 dB and 266.28 K @ 50K, respectively.This paper presents the design and simulation of a 220-GHz miniaturized slot-antenna-coupled high-temperature superconducting (HTS) mixer, which integrates the HTS junction and the choke filter on one single substrate. The presented mixer utilizes$\mathbf{Bi_{2}}\mathbf{Sr_{2}}\mathbf{CaCu}2\mathbf{O_{8}}$(BSCCO) intrinsic Josephson junction array as the nonlinear mixing device. To compensate the parasitic capacitance of the BSCCO junction, a short transmission line is used as an inductance for improving impedance matching between the slot antenna and the BSCCO Josephson junction array. The simulation results show that the proposed mixer achieves a conversion gain and noise temperature of -6.74 dB and 266.28 K @ 50K, respectively.

IEEE International Symposium on Radio-Frequency Integration Technology (RFIT)Aug 28, 20240 citations

A 220-GHz Miniaturized Antenna-Coupled Mixer Based on

\mathbf{Bi}_{2} \mathbf{Sr}_{2} \mathbf{CaCu}_{2} \mathbf{O}_{8}

Josephson Junction Array

\mathbf{Bi_{2}}\mathbf{Sr_{2}}\mathbf{CaCu}2\mathbf{O_{8}}

(BSCCO) intrinsic Josephson junction array as the nonlinear mixing device. To compensate the parasitic capacitance of the BSCCO junction, a short transmission line is used as an inductance for improving impedance matching between the slot antenna and the BSCCO Josephson junction array. The simulation results show that the proposed mixer achieves a conversion gain and noise temperature of -6.74 dB and 266.28 K @ 50K, respectively.