Eur. Phys. J. Appl. Phys. 25, 203-208 (2004)
https://doi.org/10.1051/epjap:2004008

Fast-passage microwave molecular spectroscopy with frequency sweeping

¹ Institute for Physics of Microstructures, Russian Academy of Sciences, GSP-105, Nizhny Novgorod 603600, Russia
² Institute for Theoretical Physics, University of Regensburg, 93040 Regensburg, Germany

Corresponding author: dmitry.ryndyk@physik.uni-regensburg.de

Received: 7 November 2002
Revised: 7 November 2003
Accepted: 7 November 2003
Published online: 17 February 2004

Abstract

We propose a new method of molecular microwave spectroscopy together with analysis of resonance line shapes, based on the fast passage effect. The fast passage effect is the excitation of coherent spontaneous radiation of tested molecules using a fast frequency sweep over the absorption line. We show that the line shape can be reconstructed from the received detector signal with the use of Hilbert and Fourier transformations. We find that sensitivity of a fast passage spectrometer is higher than that of an ordinary pulsed Fourier-transform spectrometer. The proposed method is a useful tool for fast analysis of gas mixtures.