ИСТИНА

With the discovery of high-temperature (high-Tc) superconductivity, it became possible, in principle, to realize Josephson junctions (JJ) with THz dynamics described by a simple resistively shunted junction (RSJ) model. These circumstances turned out to be very important when using JJs as detectors and spectrum analyzers, and they stimulated intensive studies of applications of high-Tc JJs in the terahertz frequency range (see, for example, [1]). In this report, I will present the current state of work in this direction. I will report on the progress in fabrication of epitaxial bicrystal YBa2Cu3O7-x JJs [2], development of Hilbert-transform spectrum analyzer integrated in Stirling cooler [3], the broadband JJ detector with the temperature sensitivity NET < 30 mK [4], the identification of liquids by their sub-THz reflection [5], when characterizing the output sub-THz and THz radiation from commercial sources [6], as well as new sources based on quantum cascade lasers (QCLs) [7]. Applications of high-Tc JJ in high-energy physics have been suggested and partially realized [8,9]. Advantages of Hilbert-transform spectral analysis as frequency-domain technique will be discussed and compared with conventional sub-THz and THz techniques. Perspective directions of future developments will be presented [10]. [1] Y.Y. Divin. Detection and spectroscopy of electromagnetic radiation with high-Tc Josephson junctions. Dr.Sc. Thesis. Kotelnikov Institute of Radioengineering and Electronics of RAS. Moscow, 2011. 164 pages, 41 figures, 2 tables. [2] I. Gundareva, and Y. Divin. YBa2Cu3O7-x bicrystal Josephson junctions with high IcRn-products and wide-ranging resistances for THz applications, IEEE Trans. Appl. Supercond., vol. 26, n.3, 1100204 (2016) [3] Y. Divin, A. Snezhko, M. Lyatti, U. Poppe, V. Pavlovskiy. Terahertz Applications of Hilbert-Transform Spectral Analysis. IEEE Trans. Appl. Supercond., vol. 24, N. 4, 1500807 (2014). [4] V. V. Pavlovskiy, I. I. Gundareva, O. Y. Volkov, and Y. Y. Divin. Wideband detection of electromagnetic signals by high-Tc Josephson junctions with comparable Josephson and thermal energies. Appl. Phys. Lett., vol. 116, 082601 (2020) [5] Y. Divin, A. Snezhko, U. Poppe, I. Gundareva, V. Pavlovskiy. Screening of Liquids with Quasioptical High-Tc Josephson Detectors. In: Nanotechnology in the Security Systems. (Eds: J. Bonca, S. Kruchinin; Springer, Dordrecht, 2015) Part II, Ch.15, pp.165-179. [6] A.V. Snezhko, et al. Terahertz Josephson spectral analysis and its applications. Supercond. Sci. Techn., vol. 30, 044001 (2017). [7] O. Volkov, V. Pavlovskiy, I. Gundareva, R. Khabibullin, and Y. Divin. In Situ Hilbert-Transform Spectral Analysis of Pulsed Terahertz Radiation of Quantum Cascade Lasers by High-Tc Josephson Junctions. IEEE Trans. Terahertz Sci. Techn., vol. 11, pp. 330-338 (2021) [8] Y. Divin, H.K.B. Pandya. Feasibility of ECE measurements using Hilbert-transform spectral analysis. Fusion Science and Technology, vol. 65, N.3, pp. 399-405 (2014). [9] Y.Y. Divin, et al. Hilbert-transform spectroscopy with high-Tc Josephson junctions: first spectrometers and first applications. IEEE Trans. Appl. Supercond., vol. 9, pp. 3346-3349 (1999). [10] O.Y. Volkov, I.N. Duzhikov, R.A. Khabibullin, A.N. Baranov, and Y.Y. Divin. Subterahertz difference-frequency generation in terahertz quantum cascade lasers. Appl. Phys. Lett. vol.121, 263504 (30 December 2022).