BIREFRINGENCE AND PHASE MODULATION OF SOLID-STATE LASER MEDIA - MECHANISMS FOR LASER LINE NARROWING AND MODELOCKING

We describe a mechanism for line narrowing and for modelocking lasers containing an intracavity polarization element and a birefringent medi um having nonlinear phase modulation. This type of modelocking occurs when the central laser frequency is somewhat shifted with respect to t he maximum transmission of the filter composed of the birefringent med ium and the polarizer. An additional intracavity tuner to insure this condition may be necessary. We predict the minimum temporal pulse dura tion and the maximum pulse intensity.