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arXiv · 1603.06339

Optical Activation of Germanium Plasmonic Antennas in the Mid Infrared

Marco P. Fischer·Christian Schmidt·Emilie Sakat·Johannes Stock·Antonio Samarelli·Jacopo Frigerio·Michele Ortolani·Douglas J. Paul·Giovanni Isella·Alfred Leitenstorfer·Paolo Biagioni·Daniele Brida
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Abstract

Impulsive interband excitation with femtosecond near-infrared pulses establishes a plasma response in intrinsic germanium structures fabricated on a silicon substrate. This direct approach activates the plasmonic resonance of the Ge structures and enables their use as optical antennas up to the mid-infrared spectral range. The optical switching lasts for hundreds of picoseconds until charge recombination red-shifts the plasma frequency. The full behavior of the structures is modeled by the electrodynamic response established by an electron-hole plasma in a regular array of antennas.

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Marco P. Fischer, Christian Schmidt, Emilie Sakat, Johannes Stock, Antonio Samarelli, Jacopo Frigerio, Michele Ortolani, Douglas J. Paul, Giovanni Isella, Alfred Leitenstorfer, Paolo Biagioni, Daniele Brida. 2016-06-10. Optical Activation of Germanium Plasmonic Antennas in the Mid Infrared. https://doi.org/10.1103/physrevlett.117.047401

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