Passively mode-locked diode-pumped Nd:YVO4 oscillator operating at   ultra-low repetition rate
  We demonstrate the operation of an ultra low repetition rate, high peak power, picosecond diode pumped Nd:YVO4 passively mode locked laser oscillator. Repetition rates even below 1 MHz were achieved with the use of a new design multiple-pass cavity and a semiconductor saturable absorber. Long term stable operation at 1.2 MHz, pulse duration of 16.3 ps and average output power of 470 mW corresponding to 24 KW peak power pulses is reported. This is, to our knowledge, the lowest repetition rate high peak power pulses ever generated directly from a picosecond laser resonator without cavity dumping. 
Dimitris N. Papadopoulos (LCFIO), Sebastien Forget (LCFIO), M.   Delaigue (LCFIO), Frederic Druon (LCFIO), Francois Balemboi...