RESUMO
We report on a GHz fundamental repetition rate Kerr-lens mode-locked Ho:CALGO laser emitting at 2.1â µm. The laser employs a ring cavity to increase the fundamental repetition rate to 1.179â GHz and can be made to oscillate in both directions stably with nearly identical performance: for the counterclockwise oscillation, it generates 93-fs pulses at 1.68â W of average power, whereas 92â fs and 1.69â W were measured for the clockwise operation. Our current results represent the highest average power from a 2-µm GHz oscillator and, to our knowledge, the first sub-100-fs pulse duration from a Ho-based oscillator.
RESUMO
We report on an in-band pumped soft-aperture Kerr-lens mode-locked Ho3+-doped CaGdAlO4 (Ho:CALGO) bulk laser at 2.1â µm, generating 2â W of average power with 112â fs pulses at 91-MHz repetition rate. To the best of our knowledge, this is the highest average power from a 100-fs class mode-locked laser based on a Tm3+ or Ho3+ doped bulk material. We show that the laser has excellent noise properties, with an integrated relative intensity noise of 0.02% and a timing jitter of 950â fs (rms phase noise 0.543â mrad) in the integration interval from 10â Hz to 10â MHz of offset frequency. The demonstrated combination of high average power, short pulses, and low noise makes this an outstanding laser source for many applications at 2.1â µm.