A Fast Method for Analysis of Guided Waves and Radiation From a Nano-Scale Slit Loaded Waveguide for a THz Photoconductive Source

作者：Jafarlou Saman^*; Neshat Mohammad; Safavi Naeini Safieddin

来源：IEEE Transactions on Terahertz Science and Technology, 2012, 2(6): 652-658.

DOI：10.1109/TTHZ.2012.2222880

• Dyadic Green%26apos
• s function
• millimeter wave
• photoconductor
• photomixer
• plasmonic mode
• THz source
• THz waveguide

A fast analysis method for a new terahertz waveguide for photo-mixing is proposed. The wave-guiding mixer structure is amodified 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%26apos;s function representation, a systematic approach is provided for calculating the amplitude of the guided modes that are excited by an arbitrary photocurrent.

• 出版日期2012-11