Applications of high-Tc superconductors in optoelectronics

摘要

Abstract: The discovery of high-temperature superconductors (HTS)has opened new opportunities for applications ofsuperconductors in optoelectronics. The HTS perovskitesrepresent a new class of solid-state materials,exhibiting many very interesting and potentially usefulelectronic, optical, and electro-optical properties.They also operate in the 30-80 K temperature range,where refrigeration is cheap and the parameters ofsemiconducting devices are optimal. A review of thesubstrate materials and deposition techniques suitablefor fabrication of high- quality epitaxial HTS filmsfor electronic and optoelectronic applications isgiven. Laser processing techniques of HTS films arepresented, with a special emphasis put on the laserwriting method, which enables definition ofsuperconducting and nonsuperconducting regions in thesame, epitaxial HTS film. Two possible approaches forthe development of a complete optoelectronic systemwith the elements based on the HTS films andoperational at liquid- nitrogen temperatures arepresented. The first approach consists of manufacturingthe devices made of conventional electro-opticmaterials and containing HTS transmission lines andelectrodes. Design and properties of ultrafast HTSinterconnects are discussed, and a new concept of theMach-Zehnder-typeYBa$-2$/Cu$-3$/O$-7$MIN@y$/-on-LiNbO$-3$/ opticalmodulator is introduced. The second, more futuristicapproach, is to exploit contrasting properties of theoxygen-poor and oxygen-rich HTS phases to fabricatenovel, monolithic devices. Recent experiments arediscussed, which reveal intriguing optical propertiesof HTS films, and are most relevant for the developmentof all-HTS optoelectronic devices. Several practicaldevices, such as high-frequency modulators,ultrafast-pulse generators, and sensitivephotodetectors will be presented.!60