Time meets frequency: phase stabilization of ultrafast pulses and optical frequency metrology with modelocked lasers

Recently there has been a remarkable convergence between ultrafast laser technology and precision optical frequency metrology, two fields that at first glance seem very disparate. This has led to a paradigm shift in optical frequency metrology by replacing complex frequency chains with a single modelocked laser. It has also enabled the first generation of optical clocks. It promises to have future impact on ultrafast physics, particularly extreme nonlinear optics and coherent control. The basic concepts for self-reference detection and stabilization of modelocked lasers are presented. Recent measurements using this technique are reviewed and the time domain implications demonstrated.