Investigation of negative feedback regimes for generation of compressed pulses

The results of optimisation of active and passive negative feedback (NF) fo r generation of stable compressed picosecond pulse trains in Nd:glass and N d:YAG lasers using a modulator driven by fast photomultiplier and a GaAs pa ssive element are presented, Conditions of prolonged pulse trains generatio n with the duration of trains varied from 0.3 mu s to 200 mu s depending on parameters of active NF were investigated. Generation of long (1000 ns) pu lse trains in passive NF regime was obtained. Pulse compression in active a nd passive NF regimes (from 8 ps to 1.4 ps and from 35 ps to 13 ps, respect ively) was achieved.