Open AccessAn optogalvanic gas sensor based on Rydberg excitations
Author(s) -
Johannes Schmidt,
Yannick Münzenmaier,
Patrick Kaspar,
Patrick Schalberger,
Holger Baur,
Robert Löw,
Norbert Fruehauf,
Tilman Pfau,
Harald Kübler
Publication year - 2020
Publication title -
journal of physics. b, atomic molecular and optical physics/journal of physics. b, atomic, molecular and optical physics
Language(s) - English
Resource type - Journals
eISSN - 1361-6455
pISSN - 0953-4075
DOI - 10.1088/1361-6455/ab728e
Subject(s) - rydberg formula , excited state , atomic physics , rubidium , excitation , chemistry , sensitivity (control systems) , rydberg state , ionization , trace gas , physics , ion , potassium , quantum mechanics , electronic engineering , engineering , organic chemistry
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 (N 2 ). 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.