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Updated: May 21, 2026
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Design, Fabrication, and Experimental Characterization of Plasmonic Photoconductive Terahertz Emitters
Published on: July 8, 2013
Mid-infrared designer metals
1Department of Electrical and Computer Engineering, University of Illinois Urbana Champaign, Urbana, Illinois 61801, USA. slaw2@illinois.edu
Optics Express
|June 21, 2012
Summary
Highly-doped semiconductor epilayers show promise for mid-infrared plasmonic devices. Researchers fabricated and tested subwavelength disks, observing localized plasmonic resonances tunable across the mid-infrared spectrum.
Area of Science:
- Materials Science
- Optics
- Nanotechnology
Background:
- Semiconductor epilayers are crucial for advanced optical applications.
- Mid-infrared (MIR) plasmonics offers unique opportunities for sensing and spectroscopy.
- Controlling material properties is key to designing effective plasmonic devices.
Purpose of the Study:
- To investigate highly-doped indium arsenide (InAs) epilayers as building blocks for MIR plasmonic structures.
- To demonstrate the tunability of plasma frequency in InAs epilayers for MIR applications.
- To fabricate and characterize subwavelength InAs disks for localized plasmonic resonances.
Main Methods:
- Growth of highly-doped InAs epilayers using molecular beam epitaxy (MBE).
- Characterization via Hall measurements and various optical techniques.
- Fabrication of subwavelength disks and comparison of experimental results with numerical simulations and a quasistatic dipole model.
Main Results:
- Demonstrated controlled plasma frequency across a broad range of MIR frequencies in InAs epilayers.
- Successfully fabricated subwavelength InAs disks exhibiting localized plasmonic resonances.
- Achieved good agreement between experimental observations, numerical simulations, and theoretical models.
Conclusions:
- Highly-doped InAs epilayers are viable building blocks for MIR plasmonic devices.
- The plasma frequency of these epilayers can be precisely tuned for MIR applications.
- Fabricated InAs disks show promise for creating tunable MIR plasmonic structures.
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