Title :
A Fast Method for Analysis of Guided Waves and Radiation From a Nano-Scale Slit Loaded Waveguide for a THz Photoconductive Source
Author :
Jafarlou, Saman ; Neshat, Mohammad ; Safavi-Naeini, Safieddin
Author_Institution :
Dept. of Electr. & Comput. Eng., Univ. of Waterloo, Waterloo, ON, Canada
Abstract :
A fast analysis method for a new terahertz waveguide for photo-mixing is proposed. The wave-guiding mixer structure is a modified parallel plate waveguide (PPWG) in which the top plate is replaced by a periodic array of sub-wavelength nano-slits. The substrate of the PPWG is made of a fast photoconductive material in which laser photomixing/absorption occurs. The characteristic equation of the modified PPWG when used as a THz waveguide is derived analytically, and its guided modes are studied in details over THz range of frequencies. The accuracy of the analytical results are verified by comparison with full-wave numerical simulations. The criteria for choosing the suitable mode for photomixing application are also discussed. Finally, based on dyadic Green´s function representation, a systematic approach is provided for calculating the amplitude of the guided modes that are excited by an arbitrary photocurrent.
Keywords :
Green´s function methods; absorption; numerical analysis; parallel plate waveguides; photoconducting materials; terahertz materials; PPWG; THz photoconductive source; absorption; arbitrary photocurrent; characteristic equation; dyadic Green´s function representation; fast analysis method; fast photoconductive material; full-wave numerical simulations; guided wave analysis; laser photomixing; modified parallel plate waveguide; nanoscale slit loaded waveguide; radiation analysis; subwavelength nanoslit periodic array; systematic approach; terahertz waveguide; waveguiding mixer structure; Dispersion; Green´s function methods; Millimeter wave technology; Photoconductivity; Plasmons; Propagation constant; Dyadic Green´s function; THz source; THz waveguide; millimeter wave; photoconductor; photomixer; plasmonic mode;
Journal_Title :
Terahertz Science and Technology, IEEE Transactions on
DOI :
10.1109/TTHZ.2012.2222880
