True fundamental solitons in a passively mode-locked short-cavity Cr^4+:YAG laser

We demonstrate a self-starting, passively mode-locked short-cavity Cr⁴⁺:YAG laser that supports fundamental intracavity solitons over wide ranges of cavity group-velocity dispersion and pulse energies. The total dispersion and nonlinear effects are small enough that stable, $N=1$ soliton pulses are generated. Equally spaced multiple pulsing is also observed, with fundamental soliton behavior preserved. Regions of bistability exist where, at a constant cavity dispersion, the laser can produce transform-limited pulses of a different width and energy. The laser produces 200-fs pulses at approximately 0.9-, 1.8-, and 2.7-GHz repetition rates with a total of 82 mW of average output power.