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arXiv · 2101.10108

Theoretical proposal for the experimental realisation of a monochromatic electromagnetic knot

R. P. Cameron·W. Löffler·K. D. Stephan
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Abstract

We propose an antenna designed to generate monochromatic electromagnetic knots and other "unusual electromagnetic disturbances" in the microwave domain. Our antenna is a spherical array of radiating dipolar elements configured to approximate the desired electromagnetic field near its centre. We show numerically that a specific embodiment of the antenna with a radius of 61.2 cm and only 20 element pairs driven at a frequency of 2.45 GHz can yield linked and torus-knotted electric and magnetic field lines approximating those of an "electromagnetic tangle": a monochromatic electromagnetic knot closely related to the well-known Rañada-Hopf type electromagnetic knots but simpler in its construction. The antenna could be used to locally excite plasmas.

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R. P. Cameron, W. Löffler, K. D. Stephan. 2021-05-11. Theoretical proposal for the experimental realisation of a monochromatic electromagnetic knot. https://doi.org/10.1088/2040-8986%2Fabfc33

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