Publications

Dipole radiation near a reflecting corner.

Faculty Author(s): Li, Xin
Student Author(s): -
Department: PHYS
Publication: Journal of Applied Physics
Year: 2020
Abstract: We consider a radiating electric dipole, located near the joint of two orthogonal mirrors. The field lines of energy flow in the neighborhood of the dipole have an intriguing structure due to interference between the dipole radiation and the reflected light by the mirrors. Numerous singularities and vortices appear in the sub-wavelength region between the dipole and the surfaces. We present a method to find the locations of the vortices and singularities without regard to the details of the flow pattern. The radiation field induces a surface current density in the mirrors. The direction of the current is predominantly in the radial direction for a linear dipole, but it alternates between outgoing and incoming across singular curves. We show that the field line pattern expands with a phase velocity larger than the speed of light. For a circular dipole, there appears a spiral which runs inward. The current initially flows in along this spiral. Then the current leaves again along an outgoing spiral, which spirals inside the incoming spiral. Current can flow from one mirror to the other, and we show that the current always crosses the intersection line at a 90° angle. [ABSTRACT FROM AUTHOR] Copyright of Journal of Applied Physics is the property of American Institute of Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Link: Dipole radiation near a reflecting corner.