Multi-kilohertz repetition rate Ti:sapphire amplifier based on down-chirped pulse amplification

We present a novel ultrafast multipass laser amplifier design optimized for sub-millijoule output energy and capable of being operated at repetition rates exceeding 40 kHz. This ti: sapphire based system makes use of a grism based stretcher, a cryogenically cooled ti: sapphire crystal and an astigmatically compensated multipass amplifier design that allows for pumping with significantly lower pump pulse energies than has been demonstrated to date. We also make use of the downchirped pulse amplification scheme to minimize loss in the pulse compression process. Preliminary experiments demonstrate an output pulse energy of 290 mu J at 10 kHz and 270 mu J at 15 kHz with a pulse duration of 36 fs. (c) 2006 Optical Society of America.