Eur. Phys. J. D 2, 5-10 (1998)
https://doi.org/10.1007/PL00021560

Electromagnetically induced transparency in a sodium vapour cell

Institut für Experimentalphysik, Technische Universität Graz, 8010 Graz, Austria

Corresponding author: ^a windholz@fexphds01.tu-graz.ac.at

Received: 17 December 1997
Accepted: 6 March 1998
Published online: 12 July 2013

Abstract

We report on an investigation of electromagnetically induced transparency (EIT) in sodium vapour. In our experiment, sodium atoms are excited on the D ₁-line with laser radiation containing two components with a frequency difference close to that of the two hyperfine ground states of sodium (1.772 GHz). Such an excitation leads to coherent trapping of atomic population in "dark" superpositional states, which dramatically reduces the absorption of light. A frequency transparency window is measured to have a subnatural width, which is a clear indication of coherent population trapping. Dependence of EIT on laser frequencies and intensities, on the magnetic field strength as well as on the temperature of the sodium vapour is studied.