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Title: Terahertz detectors for long wavelength multi-spectral imaging.

Abstract

The purpose of this work was to develop a wavelength tunable detector for Terahertz spectroscopy and imaging. Our approach was to utilize plasmons in the channel of a specially designed field-effect transistor called the grating-gate detector. Grating-gate detectors exhibit narrow-linewidth, broad spectral tunability through application of a gate bias, and no angular dependence in their photoresponse. As such, if suitable sensitivity can be attained, they are viable candidates for Terahertz multi-spectral focal plane arrays. When this work began, grating-gate gate detectors, while having many promising characteristics, had a noise-equivalent power (NEP) of only 10{sup -5} W/{radical}Hz. Over the duration of this project, we have obtained a true NEP of 10{sup -8} W/{radical}Hz and a scaled NEP of 10{sup -9}W/{radical}Hz. The ultimate goal for these detectors is to reach a NEP in the 10{sup -9{yields}-10}W/{radical}Hz range; we have not yet seen a roadblock to continued improvement.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Sandia National Laboratories
Sponsoring Org.:
USDOE
OSTI Identifier:
921735
Report Number(s):
SAND2007-6354
TRN: US0802157
DOE Contract Number:
AC04-94AL85000
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; FIELD EFFECT TRANSISTORS; PLASMONS; SENSITIVITY; SPECTROSCOPY; WAVELENGTHS; Spectral analysis-Instruments; Spectrometer.; Plasmons (Physics); Spectroscopy.; Spectral data.

Citation Formats

Lyo, Sungkwun Kenneth, Wanke, Michael Clement, Reno, John Louis, Shaner, Eric Arthur, and Grine, Albert D. Terahertz detectors for long wavelength multi-spectral imaging.. United States: N. p., 2007. Web. doi:10.2172/921735.
Lyo, Sungkwun Kenneth, Wanke, Michael Clement, Reno, John Louis, Shaner, Eric Arthur, & Grine, Albert D. Terahertz detectors for long wavelength multi-spectral imaging.. United States. doi:10.2172/921735.
Lyo, Sungkwun Kenneth, Wanke, Michael Clement, Reno, John Louis, Shaner, Eric Arthur, and Grine, Albert D. 2007. "Terahertz detectors for long wavelength multi-spectral imaging.". United States. doi:10.2172/921735. https://www.osti.gov/servlets/purl/921735.
@article{osti_921735,
title = {Terahertz detectors for long wavelength multi-spectral imaging.},
author = {Lyo, Sungkwun Kenneth and Wanke, Michael Clement and Reno, John Louis and Shaner, Eric Arthur and Grine, Albert D.},
abstractNote = {The purpose of this work was to develop a wavelength tunable detector for Terahertz spectroscopy and imaging. Our approach was to utilize plasmons in the channel of a specially designed field-effect transistor called the grating-gate detector. Grating-gate detectors exhibit narrow-linewidth, broad spectral tunability through application of a gate bias, and no angular dependence in their photoresponse. As such, if suitable sensitivity can be attained, they are viable candidates for Terahertz multi-spectral focal plane arrays. When this work began, grating-gate gate detectors, while having many promising characteristics, had a noise-equivalent power (NEP) of only 10{sup -5} W/{radical}Hz. Over the duration of this project, we have obtained a true NEP of 10{sup -8} W/{radical}Hz and a scaled NEP of 10{sup -9}W/{radical}Hz. The ultimate goal for these detectors is to reach a NEP in the 10{sup -9{yields}-10}W/{radical}Hz range; we have not yet seen a roadblock to continued improvement.},
doi = {10.2172/921735},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2007,
month =
}

Technical Report:

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