Cherenkov terahertz radiation from Dirac semimetals surface plasmon polaritons excited by an electron beam<xref rid="cpb_29_3_034101fn1" ref-type="fn">*</xref><fn id="cpb_29_3_034101fn1"><label>*</label><p>Project supported by the National Key Research and Development Program of China (Grant No. 2017YFA0701000), the National Key Scientific Instrument and Equipment Development of China (Grant No. 2018YFF01013001), and the National Natural Science Foundation of China (Grant Nos. 61701084 and 61505022).</p></fn>

Cherenkov terahertz radiation from Dirac semimetals surface plasmon polaritons excited by an electron beam**

Project supported by the National Key Research and Development Program of China (Grant No. 2017YFA0701000), the National Key Scientific Instrument and Equipment Development of China (Grant No. 2018YFF01013001), and the National Natural Science Foundation of China (Grant Nos. 61701084 and 61505022).

Zhao Tao, Wu Zhenhua^†

(a) Schematic diagram of an electron bunch moving on top of a BDS film deposited on a dielectric substrate. (b) The dispersion curves. The solid red line represents the dispersion curve of a moving electron beam. (c) Fourier spectra of the radiation intensity. (d) The contour map of the electric field intensity E_z in the y–z plane. The beam velocity was 0.4c, the permittivity of the substrate was 12, and the distance between the electron beam and the surface of the BDS film was y₀ = 0.1 μm. The other parameters were the same as those used in Fig. 1.