Harnessing the power and structure of light

Light revolutionized our vision of technology. Carrying five internal degrees of freedom, it offers unlimited capabilities in light-matter interactions. The recent advances in coherent light sources enable remarkable progress in harnessing degrees of freedom and boost light-induced applications. The further increasing demand in controlling the light states catalyzes technological innovations in laser-based systems. In this presentation, I will focus on our efforts in developing high-power laser systems based on the active double-clad tapered fibers with excellent control of light states in temporal and spatial domains. The special geometrical architecture of tapered fibers enables the direct amplification of picosecond pulses from tens of milliwatts to over half-kW levels in a single amplification stage preserving excellent output spatial and polarization characteristics. The spun tapered fiber features low birefringence resulting in improved polarization stability at high power levels. Moreover, this geometrical architecture empowers the generation and simultaneous amplification of structured light, maintaining both complex polarization profiles and spatial intensity distribution. Our recent results show that the structured light can also be coherently combined, enabling power scaling in analogy with the Gaussian beam and providing beams with higher modal purity.