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arXiv · 2403.10690

Nonlinearity-induced Scattering Zero Degeneracies for Spectral Management of Coherent Perfect Absorption in Complex Systems

Cheng-Zhen Wang·John Guillamon·William Tuxbury·Ulrich Kuhl·Tsampikos Kottos
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Abstract

We develop a Coherent Perfect Absorption (CPA) protocol for cases where scale invariance is violated due to the presence of nonlinear mechanisms. We demonstrate, using a microwave setting that lacks geometrical symmetries, that the nonlinearity offers new reconfigurable modalities: the destruction or formation of nonlinear CPAs (NL-CPAs), and their frequency positioning and bandwidth management using the incident power as a control knob. The latter occurs via the formation of exceptional point degeneracies of the zeroes of nonlinear scattering processes. Our results establish NL-CPA protocols as a versatile scheme for the creation of reconfigurable hot/cold-spots in complicated enclosures (e.g. buildings or vessels) with applications to next-generation telecommunications, long-range wireless power transfer, and electromagnetic warfare.

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physics.opticscond-mat.dis-nnnlin.CDphysics.app-ph

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Cheng-Zhen Wang, John Guillamon, William Tuxbury, Ulrich Kuhl, Tsampikos Kottos. 2024-03-15. Nonlinearity-induced Scattering Zero Degeneracies for Spectral Management of Coherent Perfect Absorption in Complex Systems. https://doi.org/10.1103/physrevapplied.22.064093

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