Required operating wavelengths in GaAs injection lasers have generally determined the operating temperature, preventing the use of optimum refrigeration systems. Recent advances in GaAIAs injection lasers have produced high efficiency lasers with selectable wavelengths from 0.8 microm to 0.9 microm. This paper discusses the refrigeration considerations for GaAIAs lasers. The basis for selecting the thermoelectric refrigerator is presented and the solution of the optical-electronic interface problems are discussed. Finally, the actual design and performance characteristics of the individual laser arrays and a thermoelectrically cooled, GaAIAs illuminator are described.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1364/AO.9.002249 | DOI Listing |
Chirality
January 2025
JASCO Corporation, Japan.
A vibrational circular dichroism (VCD) instrument having a thermoelectrically cooled detector (denoted as a TEC unit) was constructed in this study. An electronic device, instead of liquid nitrogen, was employed in the instrument to cool the detector. The feasibility of the system was examined by recording the VCD spectra of liquid pinenes and insect wings.
View Article and Find Full Text PDFNanomaterials (Basel)
October 2024
Institute of Electronics and Telecommunications, Peter the Great St. Petersburg Polytechnic University, 195251 St. Petersburg, Russia.
The possible contribution of phonon drag effect to the thermoelectrically sustained potential of a heated nanoisland on a semiconductor surface was estimated in a first principal consideration. We regarded electrons and phonons as interacting particles, and the interaction cross-section was derived from the basic theory of semiconductors. The solution of the equation of motion for average electrons under the simultaneous action of phonon drag and electric field gave the distributions of phonon flux, density of charge carriers and electric potential.
View Article and Find Full Text PDFWe introduce a dual-comb spectrometer based on erbium fiber oscillators at 250 MHz that operates in the 7.5-11.5 µm spectral range over optical bandwidths up to 9 THz with a multi-kHz acquisition rate.
View Article and Find Full Text PDFData Brief
June 2023
Electric Power Research Institute (EPRI), 3420 Hillview Ave, Palo Alto, CA 94304, USA.
The data presented here consists of library spectra obtained for use with a laser absorption spectroscopy gas sensor. The spectra include absorbance data for SO, SO, HO and HSO at 300° C and 350° C temperatures in two wavelength bands, 7-8 µm and 8-9 µm. Datasets were collected in a heated multi-pass absorption Herriott cell using two tunable external cavity quantum cascade laser sources, with the resulting transmission signal measured using a thermoelectrically cooled MCT detector.
View Article and Find Full Text PDFMagn Reson Imaging
July 2023
Beijing Limecho Technology Co., Ltd., Beijing 102299, China. Electronic address:
Time-domain NMR has been extensively utilised to study various characteristics of fluid-saturated porous,materials for instance their mobility, dynamics, stiffness, viscosity and rigidity features, particularly for solid hydrocarbons, rubbers and other polymers. As a unique time-domain technique available for over 30 years, NMR cryoporometry (NMRC) may be used to obtain pore-size distributions of the measured samples. To accurately control the sample temperature, a Peltier thermo-electrically cooled variable temperature probe has been developed and integrated with a highly compact precision NMR time-domain relaxation spectrometer, therefore providing the community with a high-performance instrument for NMR Cryoporometry.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!