Nonlinear propagation of a-few-optical-cycle pulses in a photonic crystal fiber-experimental and theoretical studies beyond the slowly varying-envelope approximation

Abstract

Abstract-The evolution of spectral and temporal profiles of 4.5 optical-cycle pulses propagating near zero-dispersion wavelength (ZDW) in a photonic crystal fiber is investigated experimentally and theoretically beyond the slowly varying-envelope approximation. The excellent agreement between the experimental and theoretical results suggests that the observed gap in the spectral profile, the most distinctive feature, originates from the self-steepening effect. This effect intensifies the spectral component shorter than the ZDW with the decay of higher order solitons and consequently induces the intrapulse four-wave mixing (FWM). As a result, the anti-Stokes and Stokes components produced by the FWM enables us to generate a supercontinuum from 480 to 1020 nm.Index Terms-A-few-cycle pulse propagation, four-wave mixing (FWM), optical solitons supercontinuum generation, photonic crystal fiber, self steepening (SST), slowly varying envelope approximation (SVEA) free.

Sub-5-fs Pulse Compression of Laser Output Using Photonic Crystal Fiber with Short Zero-Dispersion Wavelength

“…The observed spectrum was strongly modulated in the region from 680 to 900 nm (region A), where a very high order soliton breaks up into numerous weaker pulses and then propagates partially as solitons and partially as dispersive radiation. 6,7) On the other hand, in the shorter-wavelength region of normal dispersion, the usual gently sloping broadening of the spectrum due to self-phase modulation occurs. The M-SPIDER signal measured from 300 to 445 nm with a delay time of 873 fs and a spectral shear =2 of 8.20 THz shows sharp spectral features in the region from 373 to 427 nm, corresponding to region A [Fig.…”