Irradiation of HTS Josephson junctions with the surface wave resonator

Abstract

Microwave properties of the surface wave resonator (SWR) consist of high-temperature superconductor (HTS) film on dielectric substrate were investigated. The analysis of the systems is made for continuous HTS film and for a film with an array of HTS Josephson junctions (JJ). In the last case it was revealed the Josephson junction synchronization effect, occurred under the influence of electromagnetic field (EMF) of the SWR. Due to this effect it is possible to make devices with synchronized array of junctions. The Josephson generation of HTS JJ array, embedded in the SWR is investigated in the X-band.The essential advantages of thin film HTS surface wave resonators as the basic elements for the coupling optimization of EMF and HTS JJ arrays were shown in [I-51. These systems have a high homogeneity and a great value of microwave current in the film plane. They are of a great interest of creation the devices with HTS JJ arrays of ,low and medium integration levels [6, 7, 81 such as voltage standards, tunable generators and microwave detectors.The microwave properties of the SWR can be qualitatively deduced fiom the parallel-plate transmission line model with losses [9]. In general case the parallel-plate transmission line consists of two plane conductors of unequal thickness spaced by a dielectric layer. As it was shown in [lo] the eigenwaves in this system are Swihart-plasmon modes. For the definite model parameter relations these eigenwaves are. converted to wellknown cases of Swihart waves [ l l ] (approximation kd&<<1) or surface waves -plasmons [12] (approximation kd& >> 1 ) (Fig. 1). In the last case the surface electromagnetic wave propagates in the vicinity of one conducting strip, even if no second strip is present. The model is also adequate if the strips have infinite conductance, when the Swihart-plasmon mode is converted to an ordinary TEM wave, which exists only for two-strip systems (Fig. la).When the parallel-plate transmission line has finite size I along the propagation direction z, the transmission line is transformed to a resonator. Its fundamental mode is determined by this longitudinal size 1.The examples of SWR are single metal plate or film, plate or film on a dielectric substrate, metal-dielectric-metal structures and so on [ l , 31. In the particular case half-wave SWR can be created as a sandwich of HTS thin film * z z >Figure 1. Distribution,of electric field in the parallelplate transmission line: TEM wave (a); Swihart wave (b); surface plasmon (c); Swihart -plasmon wave (d).

Microwave Magnon-Plasmon-Polaritons in the Ferromagnetic Metal–Screened Insulator Structure

“…Provided the conditions → ∞ and = 1, the examined resonance structure is the plate of a real metal with finite lateral dimensions × and is located in the free space. This structure is the simplest case of the SEMWR on the basis of a conducting plate (film) with a finite thickness [6,8,9,12,13]. But if < ∞ and ≥ 1, the RFM-NMI-IM resonance structure can be identified with an SEMWR (layer of a real metal on a dielectric substrate) arranged on the wall surface in a rectangular waveguide (the ideal metal screen).…”

“…Note that just such SEMWRs on the basis of a conducting film deposited onto a dielectric substrate are used in practice. For the efficient excitation of oscillations in the SEMWR, the latter is mounted inside a rectangular waveguide [6][7][8][9][10][11][12][13].…”

“…For this purpose, let us make the following substitutions in expressions (2): the substitution e −i → sin( ) in the components and and the substitution e −i → cos( ) in the component , assuming ≈ / . In addition, we should take into account that the distribution of the electromagnetic field in the RM-SI resonance structure does not depend on the coordinate (as is indicated by the index = 0 for the fundamental SEMWR mode E 01 ; note that this mode was experimentally determined to be quasi-uniform in the SEMWRs [6,8,9,13]). Taking the aforesaid into account, we obtain the following expressions for the electromagnetic field components at the fundamental mode of oscillations in the SEMWR, E 01 :…”

“…is the relative dielectric permittivity of the medium: = ( ) for the real metal, = for the insulator, and → −∞ √ −1 for the ideal metal quency interval [6,7]. This system turned out convenient for developing various superconducting devices with Josephson junctions [8][9][10][11] (see also recent reviews [12,13]). The theoretical prediction of surface plasmons [14], the quasiparticles that describe collective oscillations of the electron density near the conducting-medium boundary, became a powerful impetus for intensifying the SEMW studies.…”

Recent Trends in Microwave Magnetism and Superconductivity

“…In particular, it was shown that, in a below-cutoff rectangular waveguide, the spectrum of SEWR natural oscillations is substantially rarefied, which can be used for the creation of more efficient microwave devices [25,26]. The obtained results were summarized in [23,24,27].…”