Surpassing soliton compression limits in anomalous dispersion high-power erbium fiber comb

Abstract

Femtosecond power scaling in anomalous dispersion waveguides like telecom fiber is limited by runaway pulse collapse. We achieve an order of magnitude increase over previous femtosecond erbium fiber lasers by using phase-only pulse shaping in a stretcher fiber Bragg grating and identify a truncated Jacobi elliptic function pulse shape with better nonlinear compression characteristics than standard pulses. We generate 1560 nm, 340 nJ, 63 fs, 2.4 MW peak power pulses at 25 MHz repetition rate with standard single-mode fiber and a chirped mirror pair rather than bulk gratings. At a higher 100 MHz repetition rate, we verify frequency comb stability with 110 nJ, 62 fs pulses at 11 W average power. This record output can combine comb precision with strong field physics, and the method broadly applies to improving ultrafast laser sources.