Graph theory approach to exceptional points in wave scattering
نویسندگان
چکیده
Abstract In this paper, we use graph theory to solve wave scattering problems in the discrete dipole approximation. As a key result of work, presence active scatterers, present systematic method find arbitrary large-order zero eigenvalue exceptional points (EPs). This is achieved by solving set non-linear equations that interpret, picture, as vanishing sums events. We then show how total field system responds parameter perturbations at EP. Finally, investigate sensitivity power output imaginary perturbation design frequency. can be employed trade for different dissipation balance system. The purpose results paper manifold. On one hand, aim shed light on link between and scattering. other application all those settings where EPs play unique role like coherent perfect absorption structures.
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ژورنال
عنوان ژورنال: Journal of Physics A
سال: 2023
ISSN: ['1751-8113', '1751-8121']
DOI: https://doi.org/10.1088/1751-8121/acdb13