high energy square-shaped pulses in an all-fiber mode-locked Double Clad (DC) erbium-
ytterbium (Er-Yb) figure-8 laser (F8L) is presented. The laser was capable of generating 170
ns pulses with an average power of 1.7 W at 800 kHz repetition rate, which corresponds to a
record pulse energy of 2.13 μJ, achieved directly from the resonator, without Q-switching,
cavity dumping or additional amplifiers. Unique circulator-based out-coupling of high energy …