117-mJ pulse energy, high average power, Q-switched Yb-doped 49-core fiber amplifier

Abstract

This work presents the simultaneous scaling of the average power and pulse energy emitted by multicore fiber laser systems. This is achieved through two series of experiments that use a generation of Yb-doped multicore fiber amplifiers with 49 cores, seeded by a Q-switched multicore fiber laser. One of the main results of these experiments is a total pulse energy of up to 117 mJ at a repetition rate of 5 kHz in quasi-continuous pumping operation. In a different experiment with a smaller core size multicore fiber, an average power of 400 W was achieved at a repetition rate of 5 kHz, corresponding to a pulse energy of 80 mJ in continuous pumping. The experimental results match our simulation predictions, providing valuable insights into the further energy scalability of Yb-doped multicore fibers.