title: Generation of high-repetition-rate femtosecond pulses from 8 to 18 microm.
abstract: We generated subpicosecond pulses from 8 to 18 mum by difference-frequency mixing in a 1-mm-thick AgGaSe(2) crystal, the 130- and 180-fs output pulses (1.45 < lambda < 1.85 mum) from an 84-MHz-repetition-rate optical parametric oscillator. Numerical simulations show that intrapulse and interpulse group velocity dispersion determine minimum pulse duration above and below 15 mum, respectively. By cross correlation (upconversion) of 10.5-mum pulses with 90-fs, 810-nm pulses in AgGaS(2), the pulse length was measured to be 310 fs in good agreement with simulations.
authors.forename: J M
authors.initials: JM
authors.lastname: Fraser
authors.forename: D
authors.initials: D
authors.lastname: Wang
authors.forename: A
authors.initials: A
authors.lastname: Haché
authors.forename: G R
authors.initials: GR
authors.lastname: Allan
authors.forename: H M
authors.initials: HM
authors.lastname: van Driel