140-GHz pulsed Fourier transform microwave spectrometer

Journal Article · Tue Jan 01 04:00:00 EST 1985 · Rev. Sci. Instrum.; (United States)

DOI:https://doi.org/10.1063/1.1138434· OSTI ID:6359093

Kolbe, W F; Leskovar, B

A pulsed microwave spectrometer operating in the vicinity of 140 GHz for the detection of rotational transitions in gaseous molecules is described. The spectrometer incorporates a tunable Fabry--Perot cavity and a subharmonically pumped superheterodyne receiver for the detection of the molecular emission signals. A 70-GHz source supplying a high-efficiency frequency doubler which is pulse modulated at 30 MHz produces sidebands of sufficient power at 140 GHz to excite the molecules. The cavity is tuned to one of the modulation sidebands. The operation of the spectrometer is illustrated by the detection of emission signals from the 6(2, 4)--6(1, 5) transition of SO/sub 2/ gas. The generation of the electric dipole analog of nuclear-magnetic-resonance (NMR) ''spin-echo'' signals by a ..pi../2-..pi.. pulse sequence is also described.

• Research Organization: Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6359093
• Journal Information: Rev. Sci. Instrum.; (United States), Journal Name: Rev. Sci. Instrum.; (United States) Vol. 56:1; ISSN RSINA
• Country of Publication: United States
• Language: English

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47 OTHER INSTRUMENTATION
CHALCOGENIDES
ELECTRONIC EQUIPMENT
ENERGY LEVELS
EQUIPMENT
EXCITED STATES
FLUIDS
FOURIER TRANSFOR
FOURIER TRANSFORMATION
FREQUENCY RANGE
GASES
GHZ RANGE
GHZ RANGE 01-100
GHZ RANGE 100-1000
INTEGRAL TRANSFORMATIONS
MEASURING INSTRUMENTS
MINERALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
POLARIZATION
SILICON COMPOUNDS
SILICON OXIDES
SPECTROMETERS
TRANSFORMATIONS