Introduction to nonlinear photonic crystal fibers

Abstract

Owing to the unique dispersion properties and high nonlinear coefficient, the small-core nonlinear photonic crystal fiber is among the most studied type in the class of microstructured fibers. We present a review of the basic aspects of nonlinear photonic crystal fibers with focus on dispersion design. The description of fiber design includes examples of fibers for use in both the telecom wavelength range and below. Moreover, we give an introduction to femtosecond supercontinuum generation and the effects of choice of pumping wavelength in relation to fiber dispersion. Finally, we present a range of application examples from the field of supercontinuum generation and telecommunication.

Alcohol sensing over O+E+S+C+L+U transmission band based on porous cored octagonal photonic crystal fiber

“…As an optical medium, photonic crystal has some identical properties [1][2][3][4][5][6][7][8][9][10][11]. The photonic crystal fibers are enormously used in the optical fiber technology due to its idiosyncratic properties.…”

“…Some identical properties are seen like as nonlinearity [1,2], high birefringence [3,4], high sensitivity [5,6], low confinement loss [7,8], improved effective area, and endlessly single mode [9][10][11]. For these reasons, PCF has drawn a great attraction among researchers.…”

Enhanced nonlinear effects in photonic crystal fibers

“…[32]. Since then, SG in PCFs has been studied extensively and the results show that a number of linear and nonlinear effects that are well-known in conventional nonlinear fiber optics [31] like group-velocity dispersion (GVD),third and higher-order dispersion, self-phase modulation (SPM), cross-phase modulation (XPM), four-wave-mixing (FWM), stimulated Raman scattering (SRS), higher-order soliton formation, self-steeping, birefringence all can come into play [21,33].…”

“…On the other hand, extremely small-core PCFs can be fabricated with enhanced nonlinearity [17]. In combination with controllable dispersion, the enhanced nonlinearity makes small-core PCFs ideally suited as nonlinear media [21], as will be exemplified in detail in this review.…”

Mode structure in continuum generation

“…The fundamental mode GVD profile of a MOF may be adjusted by changing the waveguide dispersion properties of the fibre [5]- [6] via altering the geometry, pitch and size of the air holes in the cladding region. It is possible to tailor the GVD profile such that the wavelength at the fundamental mode GVD zero is shifted from 1.3 m (in ordinary fibre) to values that are accessible to a Ti:Sapphire laser (700-900nm).…”