title: Three optical cycle mid-IR Kerr-lens mode-locked polycrystalline Cr(2+):ZnS laser.
abstract: We report Kerr-lens mode-locked polycrystalline Cr(2+):ZnS lasers at 2.4 μm central wavelength optimized for short pulse duration. By control of the second- and third-order dispersion within 500 nm bandwidth we obtained pulses of three optical cycles (<29  fs) at 100 MHz repetition rate with 0.44 W average power. The emission spectrum is 240 nm broad at -3  dB level and spans 950 nm at -30  dB level. Transform-limited 38 fs pulses were obtained at 300 MHz repetition rate with 700 mW average power. To the best of our knowledge these are the shortest reported to-date pulses from Cr(2+):ZnS and Cr(2+):ZnSe lasers.
authors.forename: Sergey
authors.initials: S
authors.lastname: Vasilyev
authors.forename: Igor
authors.initials: I
authors.lastname: Moskalev
authors.forename: Mike
authors.initials: M
authors.lastname: Mirov
authors.forename: Sergey
authors.initials: S
authors.lastname: Mirov
authors.forename: Valentin
authors.initials: V
authors.lastname: Gapontsev
mesh_terms: D002857:Chromium; D003460:Crystallization / Q000379:methods; D004735:Energy Transfer; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007259:Infrared Rays; D007834:Lasers; D007909:Lenses; D018036:Selenium Compounds / Q000737:chemistry*; D017967:Zinc Compounds / Q000737:chemistry*
chemical_list: D018036:Selenium Compounds; D017967:Zinc Compounds; D002857:Chromium; C044696:zinc selenide