Ultrafast nonlinear optics in gas-filled hollow-core photonic crystal fibers [Invited]

Abstract

We review the use of hollow-core photonic crystal fibers (PCFs) in the field of ultrafast gas-based nonlinear optics, including recent experiments, numerical modeling, and a discussion of future prospects. Concentrating on broadband guiding kagomé-style hollow-core PCF, we describe its potential for moving conventional nonlinear fiber optics both into extreme regimes-such as few-cycle pulse compression and efficient deep ultraviolet wavelength generation-and into regimes hitherto inaccessible, such as single-mode guidance in a photoionized plasma and high-harmonic generation in fiber.

Exploring new avenues in high repetition rate table-top coherent extreme ultraviolet sources

“…The pulses from the CC-FCPA are directed through a telescope and a focusing lens and are then coupled into the Kagome fiber (Figure 1). This new type of PCF offers a relatively large core (30-60 mm), low propagation loss and allows studying a variety of nonlinear effects 37 . Interestingly, the Kagome PCF has been recognized as the perfect waveguide for nonlinear compression of mJ-level pulses 38,39 , whereas conventional capillaries have extremely high propagation losses due to the required small diameter.…”

Revolver Hollow Core Optical Fibers

“…The most impressive results on supercontinuum generation were obtained in Kagome-type holy core fibers [18,71]. By varying gas pressure, the supercontinuum spanning more than three octaves from 124 to 1200 nm was obtained in [18].…”

“…Nevertheless, in the absence of evacuation at sufficiently long interaction lengths of the radiation with the gaseous medium, the nonlinear properties of the gas can exert a strong influence on the spectral-temporal characteristics of powerful ultrashort pulses [18,[71][72][73][74][75].…”

Low loss hollow optical-waveguide connection from atmospheric pressure to ultra-high vacuum

“…11 In contrast, HC-PCF provides low loss optical guidance at core diameters where a capillary would be unusable, allowing one to restrict the gas flow while maintaining good optical guidance. Optical losses of order 1 dB/m or less are routinely achieved over bandwidths of hundreds of nm in small-core (20-50 lm diameter) kagome-PCF, 12,13 with negligible bend losses. Figure 1 shows scanning electron micrographs (SEMs) of the kagome-PCFs used in the experiments reported here.…”

“…Figure 1 shows scanning electron micrographs (SEMs) of the kagome-PCFs used in the experiments reported here. The kagome-like lattice of channels in the cladding not only provides the fiber with attractive optical properties (pressure-adjustable dispersion and a high damage threshold 13 ) but also contributes significantly to the restriction of the gas flow. Even though the total area of the cladding channels is greater than that of the central core, the strong dependence of the conductance on channel diameter (Eq.…”