An optogalvanic gas sensor based on Rydberg excitations. (31st March 2020)

• Record Type: Journal Article
• Authors: Schmidt, J; Münzenmaier, Y; Kaspar, P; Schalberger, P; Baur, H; Löw, R; Fruehauf, N; Pfau, T; Kübler, H
• Is Part Of: Journal of physics. Volume 53:Number 9(2020:May 01)
• Publication Date: 2020-03-31
• Subjects: trace gas sensing -- thermal Rydberg atoms -- collisional ionization; Atoms -- Periodicals; Molecules -- Periodicals; Optics -- Periodicals; Nuclear physics -- Periodicals; 539.6
• DOI: 10.1088/1361-6455/ab728e
• Languages: English
• ISSNs: 0953-4075

Abstract

Abstract: We investigate the properties of a trace-gas sensing scheme based on Rydberg excitations at the example of an idealized model system. Rydberg states in thermal rubidium (Rb) are created using a 2-photon cw excitation. These Rydberg-excited atoms ionize via collisions with a background gas of nitrogen (N2 ). The emerging charges are then measured as an electric current, which is on the order of several picoampere. Due to the 2-photon excitation, this sensing method has a large intrinsic selectivity combined with a promising sensitivity of 10 ppb at an absolute concentration of 1 ppm. The determination of the detection limit is limited by the optical reference measurement but is at least 500 ppb.