Statistical design of chaotic waveforms with enhanced targeting capabilities

Abstract

We develop a statistical theory of waveform shaping of incident waves that aim to efficiently deliver energy at weakly lossy targets which are embedded inside chaotic enclosures. Our approach utilizes the universal features of chaotic scattering -thus minimizing the use of information related to the exact characteristics of the chaotic enclosure. The proposed theory applies equally well to systems with and without time-reversal symmetry. PACS numbers: Valid PACS appear hereThe prospect of utilizing waveform shaping of incident acoustic or electromagnetic radiation in order to efficiently direct energy to focal points, placed inside chaotic (or disordered) enclosures, has been intensely pursued during the last few years [1]. The excitement for this line of research is twofold: On the fundamental side the interesting question is to identify schemes that will allow us to utilize multiple scattering events in complex media like disordered structures or chaotic reverberation cavities in order to overcome the diffraction limit [2][3][4][5][6][7][8][9]. A successful outcome can revolutionize many applications of wave focusing in complex media, including imaging techniques [10][11][12][13] medical therapies [14], outdoor or indoor wireless communications [15] and electromagnetic warfare [16]. arXiv:1712.00510v2 [cond-mat.dis-nn]

Anomalies in light scattering

“…-symmetric Hamiltonians support a phase transition in the eigenvalue spectrum from entirely real to (partially or completely) complex ones, which occur at the so-called exceptional 16 points (EPs) [53][54][55][56][57][58]. EPs are specific to non-Hermitian systems and emerge when two (or more) eigenvalues and their corresponding eigenstates coalesce simultaneously so that the Hamiltonian becomes defective.…”

Experimental Realization of Optimal Energy Storage in Resonators Embedded in Scattering Media

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“…For systems with perfectly controlled openings, minimizing the outgoing intensity coherently enhances absorption within the medium [ 49–52 ] so that the scatterers with largest ‐factors and hence largest absorption rates may be preferentially excited. [ 53 ] However, we control only a small fraction of incoming and outgoing channels since the system is fully opened at the right side. The eigenchannel with minimal reflection is therefore mainly associated with an increase of transmission from left to right.…”

Perfect Absorption in a Disordered Medium with Programmable Meta‐Atom Inclusions

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