Frequency-tunable anti-Stokes line emission by eigenmodes of a birefringent microstructure fiber

Abstract

Birefringent microstructure fibers are shown to allow efficient generation of frequency-tunable anti-Stokes line emission as a result of nonlinear-optical spectral transformation of unamplified femtosecond Ti: sapphire laser pulses. Femtosecond pulses of 820-nm pump radiation polarized along the fast and slow axes of the elliptical core of the microstructure fiber generate intense blue-shifted lines centered at 490 and 510 nm, respectively, observed as bright blue and green emission at the output of a 10-cm microstructure fiber.

Highly efficient anti‐stokes generation in irregularly multicore microstructure fiber with double zero‐dispersion wavelengths

“…However, we also did not observe the corresponding Stokes wave of spectral peak A in the experiment at the calculated wavelength position. The reason why we did not find the corresponding Stokes wave is still not clear, but one may note the opinion in [7,14] that a high-confinement loss appear in this range and the Stokes wave was depleted.…”

“…Various types of microstructure fibers have been designed for special nonlinear optics processes [5][6][7]. In these microstructure fibers, air-cladding submicron-diameter microstructure fibers have attracted much interest on the part of researchers [8 -12], because these fibers usually have not only large nonlinearity but two zero-dispersion wavelengths (ZDWs), thus making them outstanding for efficient nonlinear-optics transformation of laser pulses within the visible and near-infrared wavelength range [13][14][15].…”

“…Generation of the anti-Stokes wave is a rather interesting nonlinear phenomenon and was observed in high-order modes in [7]. Akimov [7] described this phenomenon as a special case of phasematching four-wave mixing while the Stokes wave is depleted.…”

“…Akimov [7] described this phenomenon as a special case of phasematching four-wave mixing while the Stokes wave is depleted. In this work, we present our experimental results for highly efficient anti-Stokes generation inside a new type of irregular multicore microstructure fiber with randomly distributed cores ranging from 0.6 to 1.5 m. The anti-Stokes wave is generated in fundamental mode using unamplified femtosecond pulses.…”

Diamond-shaped-core hollow photonic-crystal fiber

“…An unprecedentedly high birefringence of 0.025 at 1550 nm has been demonstrated recently for a hollow-core PCF with a hexagonal photonic-crystal cladding [12]. Birefringent MS fibers have been shown to allow polarization control of supercontinuum generation [13,14] and frequency conversion of ultrashort pulses [15], suggesting interesting approaches to the generation of amplitude-squeezed light [16].…”