Abstract

Experiments in extreme nonlinear optics, in attosecond physics, and in frequency metrology depend on precise control of the carrier-envelope phase (CEP) of femtosecond oscillators and amplifier systems. Today intracavity fine CEP control relies mostly on pump-laser amplitude modulation [1], which is intrinsically fast but has only a limited control range and adjusts the CEP by varying the laser power. For coarse CEP adjustment with wider control range, paired fused silica wedges are used. Translating one of the wedges perpendicular to the beam path enables CEP control. Both methods, however, induce undesirable side-effects. In particular, they cause a change of the laser repetition rate. Consequently, a method for adjusting the CEP with negligible influence on other laser parameters appears highly desirable for many applications. In the following, we propose and demonstrate a mixed-material wedge pair for intracavity and extracavity CEP control. This mixed pair utilizes commonly available Schott glasses and allows for orthogonal control of carrier-envelope phase and group delay.

© 2009 IEEE