Kerr lens effects in a ring resonator with an aperture: mode locking and unidirectional operation

Abstract

A ring resonator containing a Kerr lens and a Gaussian slit is analyzed. From the point of view of Kerr lens mode locking, it is shown that a self-defocusing nonlinear element is as effective as a self-focusing one and that the positioning of the Kerr element introduces trade-offs between self-starting and operational stabilization. The nonlinearity can lead to unidirectional lasing.