Frequency-locking of organic dye lasers to atomic resonance lines

Locking of the output of a flashlamp-pumped Rhodamine 6G dye laser to the D lines of sodium vapor was achieved by means of the large Faraday rotation that occurs in the vicinity of the resonance lines. The laser beam was observed to consist spectrally of two sharp components symmetrically disposed on either side of the D1 and D2 lines. The laser doublet splitting varies with magnetic field. © 1969 The American Institute of Physics.