|   | 
Details
   web
Records
Author Kawano, Yukio; Ishibashi, Koji
Title An on-chip near-field terahertz probe and detector Type Journal Article
Year 2008 Publication Nature Photonics Abbreviated Journal (up) Nature Photon
Volume 2 Issue 10 Pages 618-621
Keywords single molecule, terahertz, THz, near-field, microscopy, imaging, 2DEG, GaAs/AlGaAs, detector, applications
Abstract The advantageous properties of terahertz waves, such as their transmission through objects opaque to visible light, are attracting attention for imaging applications. A promising approach for achieving high spatial resolution is the use of near-field imaging. Although this method has been well established in the visible and microwave regions, it is challenging to perform in the terahertz region. In the terahertz techniques investigated to date, detectors have been located remotely from the probe, which degrades sensitivity, and the influence of far-field waves is unavoidable. Here we present a new integrated detection device for terahertz near-field imaging in which all the necessary detection components — an aperture, a probe and a terahertz detector — are integrated on one semiconductor chip, which is cryogenically cooled. This scheme allows highly sensitive, high-resolution detection of the evanescent field alone and promises new capabilities for high-resolution terahertz imaging.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1749-4885 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 570
Permanent link to this record
 

 
Author Verevkin, A. A.; Ptitsina, N. G.; Chulcova, G. M.; Gol'Tsman, G. N.; Gershenzon, E. M.; Yngvesson, K. S.
Title Determination of the limiting mobility of a two-dimensional electron gas in AlxGa1-xAs/GaAs heterostructures and direct measurement of the energy relaxation time Type Journal Article
Year 1996 Publication Phys. Rev. B Condens. Matter. Abbreviated Journal (up) Phys. Rev. B Condens. Matter.
Volume 53 Issue 12 Pages R7592-R7595
Keywords 2DEG, AlGaAs/GaAs heterostructures
Abstract We present results for a method to measure directly the energy relaxation time (τe) for electrons in a single AlxGa1−xAs/GaAs heterojunction; measurements were performed from 1.6 to 15 K under quasiequilibrium conditions. We find τeαT−1 below 4 K, and τe independent of T above 4 K. We have also measured the energy-loss rate, ⟨Q⟩, by the Shubnikov-de Haas technique, and find ⟨Q⟩α(T3e−T3) for T<~4.2 K; Te is the electron temperature. The values and temperature dependence of τe and ⟨Q⟩ for T<4 K agree with calculations based on piezoelectric and deformation potential acoustic phonon scattering. At 4.2 K, we can also estimate the momentum relaxation time, τm, from our measured τe. This leads to a preliminary estimate of the phonon-limited mobility at 4.2 K of μ=3×107 cm2/Vs (ns=4.2×1011 cm−2), which agrees well with published numerical calculations, as well as with an earlier indirect estimate based on measurements on a sample with much higher mobility.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829 ISBN Medium
Area Expedition Conference
Notes PMID:9982274 Approved no
Call Number Serial 1612
Permanent link to this record
 

 
Author Shah, Jagdeep; Pinczuk, A.; Gossard, A. C.; Wiegmann, W.
Title Energy-loss rates for hot electrons and holes in GaAs quantum wells Type Journal Article
Year 1985 Publication Phys. Rev. Lett. Abbreviated Journal (up) Phys. Rev. Lett.
Volume 54 Issue Pages 2045-2048
Keywords 2DEG, GaAs/AlGaAs, heat flow, electron-phonon, hole-phonon, carrier-phonon, interactions
Abstract We report the first direct determination of carrier-energy-loss rates in a semiconductor. These measurements provide fundamental insight into carrier-phonon interactions in semiconductors. Unexpectedly large differences are found in the energy-loss rates for electrons and holes in GaAs/AlGaAs quantum wells. This large difference results from an anomalously low electron-energy-loss rate, which we attribute to the presence of nonequilibrium optical phonons rather than the effects of reduced dimensionality or dynamic screening.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 633
Permanent link to this record
 

 
Author Verevkin, A. A.; Ptitsina, N. G.; Smirnov, K. V.; Goltsman, G. N.; Gershenson, E. M.; Yngvesson, K. S.
Title Direct measurements of electron energy relaxation times at an AlGaAs/GaAs heterointerface in the optical phonon scattering range Type Conference Article
Year 1997 Publication Proc. 4-th Int. Semicond. Device Research Symp. Abbreviated Journal (up) Proc. 4-th Int. Semicond. Device Research Symp.
Volume Issue Pages 55-58
Keywords 2DEG, AlGaAs/GaAs heterostructures
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1602
Permanent link to this record
 

 
Author Verevkin, A. A.; Ptitsina, N. G.; Smirnov, K. V.; Gol'tsman, G. N.; Voronov, B. M.; Gershenzon, E. M.; Yngvesson, K. S.
Title Hot electron bolometer detectors and mixers based on a superconducting-two-dimensional electron gas-superconductor structure Type Conference Article
Year 1997 Publication Proc. 4-th Int. Semicond. Device Research Symp. Abbreviated Journal (up) Proc. 4-th Int. Semicond. Device Research Symp.
Volume Issue Pages 163-166
Keywords S-2DEG-S HEB mixers, detectors, AlGaAs/GaAs heterostructures, NbN
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1603
Permanent link to this record