title: Mid-infrared supercontinuum generation in As2S3-silica "nano-spike" step-index waveguide.
abstract: Efficient generation of a broad-band mid-infrared supercontinuum spectrum is reported in an arsenic trisulphide waveguide embedded in silica. A chalcogenide "nano-spike", designed to transform the incident light adiabatically into the fundamental mode of a 2-mm-long uniform section 1 µm in diameter, is used to achieve high launch efficiencies. The nano-spike is fully encapsulated in a fused silica cladding, protecting it from the environment. Nano-spikes provide a convenient means of launching light into sub-wavelength scale waveguides. Ultrashort (65 fs, repetition rate 100 MHz) pulses at wavelength 2 µm, delivered from a Tm-doped fiber laser, are launched with an efficiency ~12% into the sub-wavelength chalcogenide waveguide. Soliton fission and dispersive wave generation along the uniform section result in spectral broadening out to almost 4 µm for launched energies of only 18 pJ. The spectrum generated will have immediate uses in metrology and infrared spectroscopy.
authors.affiliation: Max Planck Institute for the Science of Light, Guenther-Scharowsky Str 1, 91058 Erlangen, Germany.
authors.forename: N
authors.initials: N
authors.lastname: Granzow
authors.forename: M A
authors.initials: MA
authors.lastname: Schmidt
authors.forename: W
authors.initials: W
authors.lastname: Chang
authors.forename: L
authors.initials: L
authors.lastname: Wang
authors.forename: Q
authors.initials: Q
authors.lastname: Coulombier
authors.forename: J
authors.initials: J
authors.lastname: Troles
authors.forename: P
authors.initials: P
authors.lastname: Toupin
authors.forename: I
authors.initials: I
authors.lastname: Hartl
authors.forename: K F
authors.initials: KF
authors.lastname: Lee
authors.forename: M E
authors.initials: ME
authors.lastname: Fermann
authors.forename: L
authors.initials: L
authors.lastname: Wondraczek
authors.forename: P St J
authors.initials: PS
authors.lastname: Russell
mesh_terms: D001152:Arsenicals / Q000737:chemistry*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007259:Infrared Rays; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000295:instrumentation*; D012031:Refractometry / Q000295:instrumentation*; D013440:Sulfides / Q000737:chemistry*
chemical_list: D001152:Arsenicals; D013440:Sulfides; C045816:arsenic trisulfide