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Title: Diagonal-transition quantum cascade detector

Abstract

We demonstrate the concept of diagonal transitions for quantum cascade detectors (QCD). Different to standard, vertical QCDs, here the active transition takes place between two energy levels in adjacent wells. Such a scheme has versatile advantages. Diagonal transitions generally yield a higher extraction efficiency and a higher resistance than vertical transitions. This leads to an improved overall performance, although the absorption strength of the active transition is smaller. Since the extraction is not based on resonant tunneling, the design is more robust, with respect to deviations from the nominal structure. In a first approach, a peak responsivity of 16.9 mA/W could be achieved, which is an improvement to the highest shown responsivity of a QCD for a wavelength of 8 μm at room-temperature by almost an order of magnitude.

Authors:
; ; ; ; ; ; ;  [1]; ;  [2]
  1. Institute for Solid State Electronics and Center for Micro- and Nanostructures, Vienna University of Technology, Vienna (Austria)
  2. Institute for Microelectronics, Vienna University of Technology, Vienna (Austria)
Publication Date:
OSTI Identifier:
22311009
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 9; Other Information: (c) 2014 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ABSORPTION; EFFICIENCY; EXTRACTION; TEMPERATURE RANGE 0273-0400 K; TUNNEL EFFECT; WAVELENGTHS

Citation Formats

Reininger, Peter, E-mail: peter.reininger@tuwien.ac.at, Schwarz, Benedikt, Detz, Hermann, MacFarland, Don, Zederbauer, Tobias, Andrews, Aaron Maxwell, Schrenk, Werner, Strasser, Gottfried, Baumgartner, Oskar, and Kosina, Hans. Diagonal-transition quantum cascade detector. United States: N. p., 2014. Web. doi:10.1063/1.4894767.
Reininger, Peter, E-mail: peter.reininger@tuwien.ac.at, Schwarz, Benedikt, Detz, Hermann, MacFarland, Don, Zederbauer, Tobias, Andrews, Aaron Maxwell, Schrenk, Werner, Strasser, Gottfried, Baumgartner, Oskar, & Kosina, Hans. Diagonal-transition quantum cascade detector. United States. doi:10.1063/1.4894767.
Reininger, Peter, E-mail: peter.reininger@tuwien.ac.at, Schwarz, Benedikt, Detz, Hermann, MacFarland, Don, Zederbauer, Tobias, Andrews, Aaron Maxwell, Schrenk, Werner, Strasser, Gottfried, Baumgartner, Oskar, and Kosina, Hans. Mon . "Diagonal-transition quantum cascade detector". United States. doi:10.1063/1.4894767.
@article{osti_22311009,
title = {Diagonal-transition quantum cascade detector},
author = {Reininger, Peter, E-mail: peter.reininger@tuwien.ac.at and Schwarz, Benedikt and Detz, Hermann and MacFarland, Don and Zederbauer, Tobias and Andrews, Aaron Maxwell and Schrenk, Werner and Strasser, Gottfried and Baumgartner, Oskar and Kosina, Hans},
abstractNote = {We demonstrate the concept of diagonal transitions for quantum cascade detectors (QCD). Different to standard, vertical QCDs, here the active transition takes place between two energy levels in adjacent wells. Such a scheme has versatile advantages. Diagonal transitions generally yield a higher extraction efficiency and a higher resistance than vertical transitions. This leads to an improved overall performance, although the absorption strength of the active transition is smaller. Since the extraction is not based on resonant tunneling, the design is more robust, with respect to deviations from the nominal structure. In a first approach, a peak responsivity of 16.9 mA/W could be achieved, which is an improvement to the highest shown responsivity of a QCD for a wavelength of 8 μm at room-temperature by almost an order of magnitude.},
doi = {10.1063/1.4894767},
journal = {Applied Physics Letters},
number = 9,
volume = 105,
place = {United States},
year = {Mon Sep 01 00:00:00 EDT 2014},
month = {Mon Sep 01 00:00:00 EDT 2014}
}
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