Laser shaping and optical power limiting of pulsed Laguerre-Gaussian laser beams of high-order radial modes in fullerene C₆₀

Abstract

We study here the strong nonlinear optical dynamics of nanosecond pulsed Laguerre-Gaussian laser beams of high-order radial modes with zero orbital angular momentum propagating in the fullerene C60 molecular medium. It is found that the spatiotemporal profile of the incident pulsed Laguerre-Gaussian laser beam is strongly reshaped during its propagating in the C60 molecular medium. The centrosymmetric temporal profile of the incident pulse evolves gradually into a non-centrosymmetric meniscus shape, and the on axis pulse duration is clearly depressed. Furthermore, the field intensity is distinctly attenuated due to the field intensity dependent reverse saturable absorption, and clear optical power limiting behavior is observed for different orders of the input pulsed Laguerre-Gaussian laser beams before the takeover of the saturation effect, and the lower the order of the Laguerre-Gaussian beam the less the energy transmittance.