We demonstrate controllable generation of a high-energy supercontinuum pulse of 1.8 mJ through femtosecond filamentation in prealigned diatomic molecules in air. For high-energy femtosecond laser pulses of linear polarization, the focusing condition is loosened by the cross-defocusing effect from the perpendicularly orientated molecules, which promotes the high-energy supercontinuum generation ...

Numerical simulations of third-harmonic and supercontinuum generation for femtosecond pulses propagating in air are presented which, for the first time to the best of our knowledge, do not rely on the decomposition of the total field into slowly-varying fields centered around the fundamental and third-harmonic. The simulation results are interpreted using an effective three-wave mixing approach...

We observe the coherence of the supercontinuum generated in a nanospike chalcogenide-silica hybrid waveguide pumped at 2 μm. The supercontinuum is shown to be coherent with the pump by interfering it with a doubly resonant optical parametric oscillator (OPO) that is itself coherent with the shared pump laser. This enables coherent locking of the OPO to the optically referenced pump frequency co...

We demonstrate broadband supercontinuum generation (SCG) in a dispersion-engineered silicon-germanium waveguide. The 3 cm long waveguide is pumped by femtosecond pulses at 2.4 μm, and the generated supercontinuum extends from 1.45 to 2.79 μm (at the -30  dB point). The broadening is mainly driven by the generation of a dispersive wave in the 1.5-1.8 μm region and soliton fission. The SCG was mo...

Super-flat supercontinua are generated from a double clad Tm-doped fiber amplifier. Two different laser configurations are investigated and compared. In the direct-output configuration, the long-wavelength edge of the supercontinuum spectra is extended to beyond 2.65 μm with a 10 dB bandwidth of 740 nm. In the passive pigtail configuration, the generated supercontinuum features excellent flatne...

Biophotonics and nonlinear fiber optics have traditionally been two independent fields. Since the discovery of fiber-based supercontinuum generation in 1999, biophotonics applications employing incoherent light have experienced a large impact from nonlinear fiber optics, primarily because of the access to a wide range of wavelengths and a uniform spatial profile afforded by fiber supercontinuum...

This paper analyses the advantageous features of supercontinuum (SC) generated from continuous-wave (CW) excitation. It has been shown that both the generation mechanisms and the temporal and spectral properties of supercontinuum produced with CW pump lasers are different from those of generated by means of pulsed excitation, in particular the remarkable smoothness of CW-SC spectra. We show tha...

Dramatic advances in supercontinuum generation have been made recently using photonic crystal fibers, but it is quite challenging to obtain an octave-spanning supercontinuum on a chip, partially because of strong dispersion in high-index-contrast nonlinear integrated waveguides. We show by simulation that extremely flat and low dispersion can be achieved in silicon nitride slot waveguides over ...

Cherenkov radiation from short photonic crystal fiber with a high air-fill fraction can selectively convert the 1020 nm fs pump pulses from a laser oscillator to the fundamental-mode signal pulses at a significantly shorter wavelength. Across the ultraviolet-visible spectral region, the typical fiber output is characterized by a single isolated Cherenkov band having a multimilliwatt-level avera...

The supercontinuum generated with a linearly polarized near-IR (775 nm) pump in rotated calcium fluoride is shown to have intrinsic intensity and polarization modulations. To mask the rotation of the crystal plate, we circularly polarize the pump and find greatly improved output parameters for the generated white light: intensity fluctuations of 0.5% limited only by pump laser stability, and a ...