High-power, femtosecond vortex beams generation in the visible and near-infrared region

Abstract

Ultrafast vortex beams have been successfully utilized in a wide variety of applications. Here, we report on the generation of the visible and near-infrared cylindrical vector beams with femtosecond pulse duration and tens of Watts average output power. Based on an optimized fiber chirped-pulse amplification system and second harmonic generation technology, Gaussian beams are generated at the visible and near-infrared wavelength, respectively. After mode conversion operation, the high-quality cylindrical vector beams can be obtained with a central wavelength of 1036.13 nm and maximum output power and ultrafast pulse duration of 60.49 W/824 fs for radial vector beams and 59.67 W/783 fs for azimuthal vector beams. In the visible spectral region, the output cylindrical vector beams have a maximum output power of 30.78 W (radial vector beams) and 27.46 W (azimuthal vector beams) at 515.75 nm central wavelength. The pulse durations are measured to be 262 fs for radial vector beam and 273 fs for azimuthal vector beam at the maximum output power. The results demonstrate that the proposed laser systems may pay a promising way to develop high-power femtosecond cylindrical vector beams sources in the visible and near-infrared wavelength for optical communication, super-resolution imaging and laser processing.