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Terahertz Plasmonic Field-Induced Conductivity Modulation in Gold.

ABSTRACT: We report the observation of terahertz (THz) electric field induced conductivity modulation in sub-wavelength gold plasmonic media. Through all-THz pump-probe time-resolved transmission spectroscopy, we demonstrate that the presence of induced surface charges influences near-field mediated light propagation. The phenomenon is ascribed to the enhanced metal conductivity due to enhanced surface density of conduction electrons. The surface induced charge dynamics are revealed via phase-dependent time-resolved signatures. The phenomenon is a prelude to a wide class of ultrafast active THz plasmonic devices and paves the way for plasmonic field effects devices, similar to semiconductor ones.

SUBMITTER: Elezzabi AY

PROVIDER: S-EPMC4462029 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Terahertz Plasmonic Field-Induced Conductivity Modulation in Gold.

Elezzabi A Y AY Maraghechi P P Greig S R SR

Scientific reports 20150610

We report the observation of terahertz (THz) electric field induced conductivity modulation in sub-wavelength gold plasmonic media. Through all-THz pump-probe time-resolved transmission spectroscopy, we demonstrate that the presence of induced surface charges influences near-field mediated light propagation. The phenomenon is ascribed to the enhanced metal conductivity due to enhanced surface density of conduction electrons. The surface induced charge dynamics are revealed via phase-dependent ti ...[more]

PMID: 26061122

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