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DOE OSTI · 22594542

MoS{sub 2} spaser

Jayasekara, Charith·Premaratne, Malin·Gunapala, Sarath D.·Stockman, Mark I.
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Abstract

We present a comprehensive analysis of a spaser made of a circular shaped highly doped molybdenum disulfide (MoS{sub 2}) resonator. “Spaser” is an acronym for “surface plasmon amplification by stimulated emission of radiation”–a nanoscale source of surface plasmons generated by stimulated emission in a plasmonic resonator which receives energy nonradiatively. By considering localized surface plasmon modes, operation characteristics of the model are analysed, and tunability of the design is demonstrated. We find the optimum geometric and material parameters of the spaser that provides efficient outputs and carryout a comparative analysis with a similar circular spaser made of graphene. Owing to physical and chemical properties of MoS{sub 2} and the active medium, the proposed design delivers efficient outputs in terms of spaser mode energy, operating thresholds, Q-factor, and electric field amplitude. Lower operating thresholds and higher mode energies are notable advantages of the design. Owing to having many superior features to existing similar designs, this MoS{sub 2} spaser may be much suited for applications in nanoplasmonic devices.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYAMPLIFICATIONAMPLITUDESCHEMICAL PROPERTIESDESIGNDOPED MATERIALSELECTRIC FIELDSGEOMETRYGRAPHENEMOLYBDENUM SULFIDESNANOSTRUCTURESPLASMONSRESONATORSSILICON OXIDESSTIMULATED EMISSIONSURFACES

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Jayasekara, Charith, Premaratne, Malin, Gunapala, Sarath D., Stockman, Mark I.. 2016-04-07. MoS{sub 2} spaser. https://doi.org/10.1063/1.4945378

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