mechanism for self mode locking in Ti:sapphire

Chuckwagon

I am a PHD student doing research on Ti:sapphire lasers so that when I enter the lab I have a full understanding of workings of the laser. I was wondering if anyone could go over the finer points of the mechanism of self mode locking in a Ti:sapphire laser? I have a picture in my head that involves the Kerr effect where intensity of the pump beam affects the index of refraction due to higher order effects. I understand that mode locking is just a locking of the phase of all the modes in such a way that there is constructive interference between modes producing pulses related to the width between modes. However, I am uncertain on the details especially the Fourier Transform from the time domain into the frequency domain that I was told would clarify things. Even if someone could direct me to an article or book that describes this it would be greatly appreciated.