Sub-femtosecond synchronization of KLM Ti:sapphire and Cr:Forsterite lasers

Summary form only given. Previously we have demonstrated that combined time/frequency active stabilization allows one to tightly synchronize two separate, passively modelocked femtosecond.?? This capability has allowed phase locking between the carrier waves of the two synchronized Tisapphire lasers? However,since the characteristic timing jitter of 5 fs (160 Hz bandwidth) was larger than the optical cycle period, phase locking could only occur for a few tens of microseconds at a time. Coherent optical pulse synthesis from these lasers was subsequently demonstrated.?? With substantial improvements to the passive stability of both lasers and implementation of a fast servo loop to stabilize the laser repetition frequency, it is now possible to obtain a sub-femtosecond level of timing jitter at any pre-determined timing offset between two laser pulse trains. This reliable setting of the timing offset can be electronically controlled at a high speed and with an excellent repeatability.