Physics of unbounded, broadband absorption/gain efficiency in plasmonic nanoparticles

Article

关键词: OPTICAL-PROPERTIES;    SURFACE-PLASMONS;    SPASER;    METAMATERIALS;    NANOSTRUCTURES;    ENHANCEMENT;    RESONANCES;    NANOLASER;    CYLINDER;    SHAPE;   

DOI  :  10.1103/PhysRevB.87.205418

来源: SCIE

【 摘 要 】

Anomalous resonances in properly shaped plasmonic nanostructures can in principle lead to infinite absorption/gain efficiencies over broad bandwidths of operation. By developing a closed-form analytical solution for the fields scattered by conjoined hemicylinders, we outline the fundamental physics behind these phenomena, associated with broadband adiabatic focusing of surface plasmons at the nanoscale. Over a continuous frequency range, our proposed composite nanostructure shows finite amount of absorption/amplification even in the limit of infinitesimally small intrinsic material loss/gain. Detailed physical insights are provided to justify the nature of this apparent paradox, and its counterintuitive behavior is discussed for potential applications in nonlinear optics, spasing, sensing, and energy-harvesting devices.

【 授权许可】

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