Two-fold symmetric geometries for tailored phase-matching in birefringent solid-core air-silica microstructured fibers

Abstract

The effect of birefringence in 2-fold-symmetric microstructured optical fibers on the phase matching conditions for four-wave mixing is analyzed. The three general types of four-wave mixing are considered. General features are obtained through analytic expansions of phase-matching formulas. Three commonly used designs of fibers are analyzed numerically. Particular designs allow the generation of specified wavelengths, supercontinuum or entangled photons.

Simultaneous scalar and cross-phase modulation instabilities in highly birefringent photonic crystal fiber

“…Our work follows findings from [16,17] which show that using suitably designed PCFs allows XPMI phase-matching requirements to be satisfied simultaneously for multiple frequencies, providing that the pump is located at a specific spectral region in the phase-matching diagram. We thus designed a PCF, with tailored dispersion and birefringence suitable for pumping at a wavelength of 1064 nm.…”

“…Experimental demonstrations of XPMI were easier thanks to the availability of highly birefringent fibers and were reported in the early nineties for a normal dispersion pump [9,10], although its demonstration in the anomalous dispersion pumping regime [14] had to wait almost 20 years (due to the fact that scalar MI also occurs in this configuration). The invention of photonic crystal fibers (PCFs) in the mid-nineties [15] allowed the exploration of new regimes (in which multiple sets of XPMI sidebands can be observed [16,17]) thanks to the new degree of freedom they provide in controlling their dispersion and birefringence properties [18,19]. Spontaneous XPMI [20] and PMI [21] in PCFs were first reported by pumping in the normal dispersion region.…”

Elimination of spurious modes in full-vectorial finite element method based acoustic modal solution

“…We have exploited the available two-fold symmetry and only a quarter of the waveguide is simulated. This allows a much better mesh refinement with given computer resources and also avoid degeneration of modes which have identical eigenvalues [29,30]. Besides, we have used polar mesh system which is more efficient in the distribution of discretized triangular elements along the curved interface of a circular waveguide [31].…”

Enhancement of modal stability through reduced mode coupling in a few-mode fiber for mode division multiplexing

“…1 shows the normalized dominant H y field variation of these four LP 01 , LP 11 , LP 21 and LP 02 modes along the radial axis. For an accurate modal solution, the existing symmetry conditions of the fiber are exploited and only quarter of the structure is simulated [18]. The complete H y field contours of these modes are also shown as insets in Fig.…”

“…Recently, a high and low index strip doped technique was proposed to increase the effective index difference between the higher order LP 18 , LP 09 , LP 19 modes of a MMF for high power laser transmission systems [12]. Moreover, a MIMO less elliptical core based three-mode fiber design was also proposed to suppress the inter-modal coupling by increasing the effective index difference between LP 01 , LP 11a and LP 11b modes [13].…”