Speaker: Günter Steinmeyer, Max Born Institute
Program Description
Throughout the early laser days, the relative phase between the envelope of a laser pulse and the underlying carrier wave remained a mysterious parameter. Access to this parameter was only established in the early 2000s with optical heterodyning schemes that employ two different harmonics of the laser spectrum. In the simplest case of heterodyning fundamental and second harmonic, an additional supercontinuum generation step is required to provide an octave-spanning spectrum. I will discuss how to optimize the two optical nonlinearities in the measurement scheme in order to obtain residual jitters between carrier and envelope in the sub-10-attosecond range. I will further discuss two competing control schemes, namely the traditional feedback approach and feed-forward stabilization, which corrects the carrier-envelope phase by an external acousto-optic frequency shifter. Finally, I will review methods for adjusting the carrier-envelope phase by isochronic or isodispersive prism arrangements. With the rapid technological development in the past 15 years, carrier-envelope phase control has come of age. Nevertheless, even for for Ti:sapphire lasers, there still seems to be room for improvement, in particular concerning the noise performance of amplified systems.
