Subjecting lasers to triangular modulations of the pump produces phenomena that drastically depend on the symmetry of the triangle. For instance, with slow up-rising triangles, a laser below threshold on average may deliver coherent pulses, while it does not deliver coherent pulses with fast up-rising triangles. This effect, which requires the presence of fluctuations in addition to the modulation, is reminiscent of the thermal ratchet with which a directed motion is extracted from a stochastic medium.
© 2006 Optical Society of America
Original Manuscript: March 21, 2006
Revised Manuscript: May 5, 2006
Manuscript Accepted: May 8, 2006
Published: July 10, 2006
Cristina Elena Preda, Bernard Ségard, and Pierre Glorieux, "Weak temporal ratchet effect by asymmetric modulation of a laser," Opt. Lett. 31, 2347-2349 (2006)