Microstructuring of transparent targets by a femtosecond laser

We have studied the microstructuring of the bulk of fused silica with a tightly focused femtosecond visible laser pulse. Filamentous (up to 150 gm in length and about 1 mum in diameter) broken structures have been produced inside the target. We use a novel method for evaluating the intensity of the powerful laser pulse in the bulk of transparent solid targets based on time-of-flight measurements. Self-guided propagation of a single visible femtosecond laser pulse has been examined in the tight focusing conditions as well.