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Abstract

The Sommerfeld integrals for the electromagnetic field due to a delta-function current in a horizontal electric dipole located on the planar boundary between air and a homogeneous dielectric are examined in detail. Similar to the case of the vertical dipole, the tangential electric fields consist of a delta-function pulse travelling in the air with the velocity c, the oppositely directed delta-function pulse travelling in the dielectric with the velocity c/ε^1/2 for the component E_ρ and the velocity cε^1/2 for the component E_φ, and the final static electric fields due to the charge left on the dipole. The appearance of the vertical magnetic field is similar to that of the tangential electric field. It is pointed out that the amplitude of the pulsed field along the boundary is 1/&rho², which is characteristic of the surface-wave or lateral pulse.

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Prof. Kai Li

Dr. Yi-Long Lu

Dr. Wei-Yan Pan