It is shown experimentally and theoretically that axial gas flow leads to controlled unidirectional operation of a CO2 ring laser. The direction of emission, clockwise or counterclockwise, can be selected by a slight tuning of the laser cavity (∼1% of the free spectral range). The flow velocity required for complete mode extinction depends on the relative magnitudes of the Doppler and homogeneous line widths and is ∼10 m/sec when the two are comparable.
© 1985 Optical Society of America
Original Manuscript: June 14, 1984
Manuscript Accepted: October 22, 1984
Published: January 1, 1985
J. L. Boulnois, Govind P. Agrawal, G. Bret, P. Cottin, and A. Van Lerberghe, "Gas-flow-induced controlled unidirectional operation of a CO2 ring laser," Opt. Lett. 10, 7-9 (1985)