Optical parametric generation of femtosecond pulses up to 9 mu m with LiInS2 pumped at 800 nm

We demonstrate direct access to the 4.8-9 mum spectral region with 800 nm, 1 kHz pumping of a femtosecond optical parametric amplifier based on the wi de-gap wurtzite-type LiInS2. LiInS2 did not exhibit two-photon absorption a t 800 nm and seems applicable at this pump wavelength with intensities of t he order of 100 GW/cm(2) for down-conversion of high energy ultrashort puls es up to its mid-IR edge at approximate to 12 mum. (C) 2001 American Instit ute of Physics.