Intense Cr:forsterite-laser-based supercontinuum source

Abstract

Supercontinuum pulses covering the range from 1100 to 1700 nm with energies >1.0 mJ and excellent beam quality are generated via nonlinear spectral broadening of Cr:forsterite (1240 nm, 110 fs) pulses in pressurized molecular nitrogen. Our spectra, which extend over more than half an octave, offer an attractive alternative to intense few-cycle pulse synthesis in the 1-2 μm range and lend themselves as an important add-on to Cr:forsterite laser technologies.

Mid-infrared laser filaments in the atmosphere

“…Because of the λ 2 scaling of the critical power of self-focusing P cr , using a longer-wavelength laser driver is a straightforward strategy for increasing the laser peak power and radiation energy in a single filament. Overall, filamentation experiments in high-pressure atomic and molecular gases performed using laser drivers with different carrier wavelengths [1][2][3][5][6][7][8][9][10][11][12][13][14][15] confirm this possibility (Fig. 1).…”

“…Up to now, experiments on laser-induced filamentation in the atmospheric air (white circles in Fig. 1 ) were limited to the visible and near-infrared ranges ( λ < 1030 nm), where sufficiently powerful short-pulse laser sources were available 1 2 3 5 6 7 8 9 10 11 12 13 . Most of those earlier experiments on laser filamentation in the atmosphere were performed using Ti: sapphire laser systems 1 2 3 .…”

“…1 ). However, building longer- λ alternatives to Ti: sapphire 1 2 3 and, since recently, ytterbium 9 and Cr: forsterite 10 lasers that would be capable of delivering ultrashort laser pulses with peak powers above P cr for the atmospheric air, i.e., at least a factor of λ 2 higher than the peak powers of amplified Ti: sapphire and ytterbium laser pulses used for atmospheric filamentation, is a challenging problem.…”

“…4 In Fig. 1, we present a survey of representative laser filamentation experiments [1][2][3][5][6][7][8][9][10][11][12][13][14][15] in various gases, including the atmospheric air, in a diagram where the wavelength and the peak power of laser pulses are used as coordinates. The single-filamentation regime in the atmospheric air exists in the dark area of this diagram.…”

“…1) were limited to the visible and near-infrared ranges (λ < 1030 nm), where sufficiently powerful short-pulse laser sources were available. [1][2][3][5][6][7][8][9][10][11][12][13] Most of those earlier experiments on laser filamentation in the atmosphere were performed using Ti: sapphire laser systems. [1][2][3] This class of lasers can deliver ultrashort pulses within a broad range of peak powers, allowing the generation of single and multiple filaments in air (white and rose segments of an ellipse centered at 800 nm in Fig.…”