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Updated: May 22, 2026

Determination of the Excitation and Coupling Rates Between Light Emitters and Surface Plasmon Polaritons
Published on: July 21, 2018
Four-step pulses of fractional-order surface plasmons
1School of Science, Minzu University of China, Beijing, China.
Abstract:
The 0-order transmission of a 1D metallic grating, on a high-resistivity silicon wafer in optical contact with a silicon plate, has been characterized by terahertz time-domain spectroscopy with subpicosecond resolution over a 400 ps scan range. Two new long-time-delay, powerful pulses are observed after the second reflected pulse. In the frequency domain, these two strong and fast-ringing structures correspond to the bandwidth ranges between the [0, 1] and [0, 2] surface plasmon modes and the range above [0, 2], respectively. A physical optics ray analysis provides an intuitive understanding of these new four-step (reflection, diffraction, total reflection, and diffraction) pulses, caused by fractional-order surface plasmon type beam coupling.
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