Superconductive Traveling-Wave Photodetectors: Fundamentals and Optical Propagation

• Published in: IEEE journal of quantum electronics 2008-07, Vol.44 (7), p.667-675
• Main Authors: Ghamsari, B.G., Majedi, A.H.
• Format: Article
• Language: English
• Subjects: Applied sciences; Cauchy integral method; Devices; Electronics; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Mathematical analysis; Mathematical models; Modulation; Optical elements, devices, and systems; Optical films; Optical propagation; Optical waveguides; Optical waveguides and coupleurs; Optics; Optoelectronic devices; Photodetectors; Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Signal generation; Signal generators; Superconducting thin films; superconductive optical waveguides; Superconductive photodetectors; Superconductivity; Superconductors; Thin film devices; Thin films; Transmission line matrix methods; traveling-wave optoelectronic devices; Ultrafast optics
• ISSN: 0018-9197; 1558-1713
• DOI: 10.1109/JQE.2008.922409

This paper studies the theory of superconductive traveling-wave photodector devices (STWPDs), as a general platform for ultrafast, ultrasensitive, and ultralow-noise optoelectronic functions such as detection, modulation, photomixing, high-frequency electrical signal generation and amplification. Principles of operation of STWPDs are discussed based on the kinetic-inductance theory of superconductive thin films and a thorough investigation of the guiding mechanism of light within this class of devices is presented. The transfer matrix method is introduced to model the superconductive optical waveguide in TWDs and an efficient numerical method based on the Cauchy integral method and the argument principle method are developed for the analysis and design of the waveguides. Moreover, several regimes of device operation will be distinguished in terms of the modal characteristics of the optical waveguide and their effects on the overall performance of the device will be highlighted.