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Updated: Jan 28, 2026

Design, Fabrication, and Experimental Characterization of Plasmonic Photoconductive Terahertz Emitters
Published on: July 8, 2013
Electric and Magnetic Hotspots via Hollow InSb Microspheres for Enhanced Terahertz Spectroscopy
Mahdiyeh Sadrara1, MirFaez Miri2
1Department of Physics, University of Tehran, P.O. Box 14395-547, Tehran, Iran.
Abstract:
We study electric and magnetic hotspots in the gap between hollow InSb microspheres forming dimers and trimers. The outer radius, core volume fraction, distance, and temperature of the microspheres can be chosen to achieve field enhancement at a certain frequency corresponding to the transition between energy levels of a molecule placed in the gap. For example, utilizing 80 μm radius spheres at a gap of 2 μm held at a temperature of 295 K, allow electric field intensity enhancements of 10-2880 and magnetic field intensity enhancements of 3-61 in the frequency window 0.35-1.50 THz. The core volume fraction and the ambient temperature affect the enhancements, particularly in the frequency window 1.5-2 THz. Electric and magnetic hotspots are promising for THz absorption and circular dichroism spectroscopy.
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