|   | 
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 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 (up) Serial 570
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 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 (up) Serial 633
Permanent link to this record
 

 
Author Shaha, Jagdeep; Pinczukb, A.; Gossardb, A. C.; Wiegmannb, W.
Title Hot carrier energy loss rates in GaAs quantum wells: large differences between electrons and holes Type Journal Article
Year 1985 Publication Phys. B+C Abbreviated Journal
Volume 134 Issue 1-3 Pages 174-178
Keywords 2DEG, GaAs/AlGaAs, heat flow, electron-phonon, hole-phonon, carrier-phonon, interactions
Abstract The first direct and separate determination of the hot electron and hot hole energy loss rates to the lattice shows unexpectedly large differences between electrons and holes in GaAs quantum wells. This large difference results from an anomalously low electron energy loss rate, which we attribute to the presence of non-equilibrium optical phonon rather than the effects of reduced dimensionality or dynamic screening. A model calculation of hot phonon effects is presented.
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 (up) Serial 634
Permanent link to this record
 

 
Author Uchiki, Hisao; Kobayashi, Takayoshi; Sakaki, Hiroyuki
Title Photoluminescence and energy‐loss rates in GaAs quantum wells under high‐density excitation Type Journal Article
Year 1987 Publication J. Appl. Phys. Abbreviated Journal
Volume 62 Issue 3 Pages 1010-1016
Keywords 2DEG, GaAs/AlGaAs, heat flow, electron-phonon, hole-phonon, carrier-phonon, interactions
Abstract The time‐resolved luminescence spectra from excited conduction subbands in three samples of multi‐quantum‐well GaAs/AlxGa1-xAs (x=0.3 and 1) semiconductors with several well widths and barrier heights were obtained under high‐density excitations by a 30‐ps pulsed laser at 532 nm, which generated electron–hole pairs to the concentration of 1010–1013/cm2 per well per pulse at 77 K. The temperature and the Fermi energy of electron were determined by fitting best the constructed time‐resolved spectrum to the observed, and the time‐dependent electron energy was obtained by using these parameters. The energy‐loss rates of hot electrons are at least twice smaller than the calculated ones induced by the electron‐polar phonon scattering, including the screening effect due to the high carrier density.
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 (up) Serial 635
Permanent link to this record
 

 
Author Shangina, E. L.; Smirnov, K. V.; Morozov, D. V.; Kovalyuk, V. V.; Gol’tsman, G. N.; Verevkin, A. A.; Toropov, A. I.
Title Frequency bandwidth and conversion loss of a semiconductor heterodyne receiver with phonon cooling of two-dimensional electrons Type Journal Article
Year 2010 Publication Semicond. Abbreviated Journal Semicond.
Volume 44 Issue 11 Pages 1427-1429
Keywords 2DEG, AlGaAs/GaAs heterostructures mixers
Abstract The temperature and concentration dependences of the frequency bandwidth of terahertz heterodyne AlGaAs/GaAs detectors based on hot electron phenomena with phonon cooling of two-dimensional electrons have been measured by submillimeter spectroscopy with a high time resolution. At a temperature of 4.2 K, the frequency bandwidth at a level of 3 dB (f 3 dB) is varied from 150 to 250 MHz with a change in the concentration n s according to the power law f 3dB ∝ n −0.5 s due to the dominant contribution of piezoelectric phonon scattering. The minimum conversion loss of the semiconductor heterodyne detector is obtained in structures with a high carrier mobility (μ > 3 × 105 cm2 V−1 s−1 at 4.2 K).
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 1063-7826 ISBN Medium
Area Expedition Conference
Notes Полоса и потери преобразования полупроводникового смесителя с фононным каналом охлаждения двумерных электронов Approved no
Call Number (up) Serial 1216
Permanent link to this record