High sensitivity microwave spectroscopy in a cryogenic buffer gas cell
| Autor: | Sandra Eibenberger, Lincoln Satterthwaite, Jessica P. Porterfield, Michael C. McCarthy, David Patterson |
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| Rok vydání: | 2019 |
| Předmět: |
Chemical Physics (physics.chem-ph)
Physics - Instrumentation and Detectors Materials science Spectrometer business.industry Amplifier Buffer gas FOS: Physical sciences Instrumentation and Detectors (physics.ins-det) Physics - Chemical Physics Optoelectronics Molecule Supersonic speed Rotational spectroscopy business Spectroscopy Instrumentation Sensitivity (electronics) |
| Zdroj: | Review of Scientific Instruments |
| ISSN: | 1089-7623 |
| Popis: | We describe an instrument which can be used to analyze complex chemical mixtures at high resolution and high sensitivity. Molecules are collisionally cooled with helium gas at cryogenic temperatures (~ 4-7 K), and subsequently detected using chirped pulse microwave spectroscopy. Here we demonstrate three significant improvements to the apparatus relative to an earlier version: (1) extension of its operating range by more than a factor of two, from 12-18 GHz to 12-26 GHz, which allows a much wider range of species to be characterized; (2) improved detection sensitivity owing to use of cryogenically-cooled low-noise amplifiers and protection switches, and (3) a versatile method of sample input that enables analysis of solids, liquids, gases, and solutions, without the need for chemical separation (as demonstrated with a 12-16 GHz spectrum of lemon oil). This instrument can record broadband microwave spectra at comparable sensitivity to high Q cavity spectrometers which use pulsed supersonic jets, but up to 3000 times faster with a modest increase in sample consumption rate. Comment: 12 pages, 6 figures |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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