A method for self-radiation of Josephson junction arrays

Abstract

We proposed a novel approach to self-radiation of Josephson junction arrays. Bicrystal Josephson junction arrays fabricated on a bicrystal substrate were integrated with a half-wavelength dipole array and embedded in a Fabry-Perot resonator. Considered as a dielectric resonator, the substrate could be stimulated to resonate in an appropriate mode at the same frequency as the Fabry-Perot resonator, which realized a coupling between Josephson junctions as well as a coupling between the junctions and microwave structures by means of a resonant interaction between junctions and resonators. Both simulations and experiments were performed. A YBCO bicrystal Josephson junction array with 166 junctions was measured at liquid nitrogen temperature. The maximal self-radiation power of 10 pW was detected at 75.2 GHz, which was in agreement with the simulation results.

An Effective Method for Improving Emissions from Intrinsic Josephson Junction Arrays of Misaligned Tl2Ba2CaCu2O8+δ Thin Films

“…However, considering the high operation temperature 78 K, the results have been improved considerably [2,9]. For a large number of serially connected junctions, many factor influence the mutual phase locking of the junctions, e.g., uniformity of the junction parameters, heating effects, operation temperature, number of activated junctions, and external magnetic field [10,12,14,15]. Therefore, it is very hard to realize synchronization of junctions even in very uniform arrays.…”

“…According to (1), the number of junctions in the microbridge can be calculated to be circa 1055 in our case. The microwave measurement system mainly included a local oscillator, isolators, attenuators, amplifiers, a mixer, a square-law detector, a measuring system of I -V characteristics, and a quasi-optical resonator in which the hemispherical mirror was replaced by a horn antenna [10]. The block diagram is shown in Fig.…”

Radiation from Intrinsic Josephson Junctions in Misaligned Tl2Ba2CaCu2O8 Thin Films

“…Figure 2 shows the block-scheme of the measurement system. For details, the readers are referred to our previous publications [13,14]; however, it might be helpful to mention the measurement process. For detecting the irradiation characteristic of the IJJs, microwave power is fed into the F-P resonator through a waveguide.…”

Possibilities to Make Panoramic Receiver–Frequency Meter in Terahertz Band Based on Josephson Junctions

“…Meanwhile, the price of these instruments is usually not affordable for most university laboratories. In case of designing low-temperature EMR structures [particularly those based on Josephson media (JM) [3]- [5]], it is essential to diminish losses in measuring transmission lines, and it is also difficult to tune the losses to the minimum due to the lack of real wideband measuring equipment.…”

“…The idea for this work came after visiting several laboratories, which had interest to realize EMR using JM [3] and practical requests for possible good but inexpensive receivers covering the short part of millimeter band with enough wide bandwidth of the intermediate frequency (IF) amplifier. These laboratories worked only with liquid nitrogen and the structures based on high-temperature superconductor (HTS) such as Bi 2 Sr 2 CaCu 2 O 8 + δ [3]- [5].…”