Year: 2025
Type: article
Abstract: The behavior of wave signals in the far zone is not only of theoretical interest but also of paramount practical importance in communications and other fields of applications of optical, electromagnetic, or acoustic waves. A long time ago, T. T. Wu [J. Appl. Phys.57, 2370 (1985)JAPIAU0021-897910.1063/1.335465] introduced models of "electromagnetic missiles" whose decay could be made arbitrarily slower than the usual inverse distance by an appropriate choice of the high-frequency portion of the source spectrum. Very recent work by Plachenov and Kiselev [Diff. Eqs.60, 1634 (2024)10.1134/S001226612460250X] introduced a finite-energy scalar wave solution, different from Wu's, decaying slower than inversely proportional with the distance. A physical explanation for the unusual asymptotic behavior of the latter will be given in this paper. Furthermore, two additional examples of scalar wave pulses characterized by abnormal slow decay in the far zone will be given, and their asymptotic behavior will be discussed. A proof of feasibility of acoustic and electromagnetic fields with the abnormal asymptotics will be described.
DOI: 10.1364/josaa.578331
Authors: Peeter Saari, Ioannis M. Besieris
Institution: Virginia Tech
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4415036067