  We report on an in-band pumped soft-aperture Kerr-lens mode-locked Ho:CALGO
bulk laser at 2.1 um, generating 2 W of average power with 112 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 950 fs
(RMS phase noise 0.543 mrad) in the integration interval from 10 Hz to 10 MHz.
The demonstrated combination of high average power, short pulses, and low-noise
make this an outstanding laser source for spectroscopy and many other
applications at 2.1 um.
