Low-temperature THz time domain waveguide spectrometer with butt-coupled emitter and detector crystal

This paper presents the design and implementation of power amplifiers using high-power gallium nitride (GaN) high electronic mobility transistor (HEMT) powerbars and monolithic microwave integrated circuits (MMICs). The first amplifier is a class AB implementation for worldwide interoperability for microwave access (WiMAX) applications with emphasis on a low temperature cofired ceramics (LTCC) packaging solution. The second amplifier is a class S power amplifier using a high power GaN HEMT MMIC. For a 450 MHz continuous wave (CW) signal, the measured output power is 5.8 W and drain efficiency is 18.5%. Based on time domain simulations, loss mechanisms are identified and optimization steps are discussed.

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Use of quantum-point-contact high-electron-mobility-transistors for time domain multiplexing of large arrays of high impedance low temperature bolometers

Review of Scientific Instruments ◽

10.1063/1.2712912 ◽

2007 ◽

Vol 78 (3) ◽

pp. 035104 ◽

Cited By ~ 4

Author(s):

S. J. C. Yates ◽

A. Benoit ◽

E. Grémion ◽

Ch. Ulysse ◽

Ph. Camus ◽

...

Keyword(s):

Low Temperature ◽

Time Domain ◽

Point Contact ◽

High Electron Mobility Transistors ◽

Quantum Point Contact ◽

High Electron ◽

High Electron Mobility ◽

Electron Mobility Transistors ◽

High Impedance ◽

Quantum Point

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Low temperature-grown GaAs carrier lifetime evaluation by double optical pump terahertz time-domain emission spectroscopy

Optics Express ◽

10.1364/oe.24.026175 ◽

2016 ◽

Vol 24 (23) ◽

pp. 26175 ◽

Cited By ~ 10

Author(s):

Valynn Katrine Mag-usara ◽

Stefan Funkner ◽

Gudrun Niehues ◽

Elizabeth Ann Prieto ◽

Maria Herminia Balgos ◽

...

Keyword(s):

Low Temperature ◽

Time Domain ◽

Emission Spectroscopy ◽

Carrier Lifetime ◽

Optical Pump ◽

Low Temperature Grown Gaas

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Real-Time Monitoring of Degradation of Zirconia Ceramic by Acoustic Emission

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.433-435.816 ◽

2013 ◽

Vol 433-435 ◽

pp. 816-820 ◽

Cited By ~ 2

Author(s):

Kai Ge Wu ◽

Chan Yang Choe ◽

Seung Mi Lee ◽

Ji Ae Yoo ◽

Chang Yong Hyun ◽

...

Keyword(s):

Acoustic Emission ◽

Low Temperature ◽

Time Domain ◽

Zirconia Ceramic ◽

X Ray Diffraction ◽

Zirconia Ceramics ◽

X Ray ◽

Ae Signal ◽

Three Stages ◽

Ae Signals

Acoustic emission (AE) technique was employed to monitor the low temperature degradation (LTD) behavior of a zirconia ceramic, which was carried out in air at 200°C. AE signals, typical waveform of which exhibited as pulse-like type, were detected during LTD and increased with the duration time of LTD. The AE signal of accumulative counts number and amplitude in time domain exhibited a roughly sigmoid variation including three stages, which reflect approximately the evolution of LTD. The AE findings were supported by X-ray diffraction (XRD) examination. It was suggested that AE technique can be used to monitor the mechanism of LTD of zirconia ceramics.

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Structural and time-domain peculiarities of the fluorescence excitation spectra of single Mg-TAP in a polymer at low temperatures

EPJ Web of Conferences ◽

10.1051/epjconf/201819004019 ◽

2018 ◽

Vol 190 ◽

pp. 04019

Author(s):

Aleksandr Savostianov ◽

Ivan Eremchev ◽

Alexei Gorshelev ◽

Sergei Orlov ◽

Oleg Korotayev ◽

...

Keyword(s):

Low Temperature ◽

Spectral Range ◽

Time Domain ◽

Low Temperatures ◽

Single Molecules ◽

Excitation Spectra ◽

Fluorescence Excitation ◽

Zero Phonon Line ◽

Broad Spectral Range ◽

Fluorescence Excitation Spectra

The results of low-temperature measurements of spectral trails (temporal evolutions of individual fluorescence excitation spectra) of single molecules Mg-tetraazaporphyrin embedded in polyisobutylene are presented. Spectral trails were recorded in a broad spectral range (up to 4000 GHz) at a temperature 6K. Spectral diffusion in a broad spectral range has been found. Individual spectra of single molecules with a broad peak shifted with respect to zero-phonon line at ~14 – 15 cm-1 were recorded. These broad peaks can be interpreted as the phonon sidebands.

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