Large topological charge optical vortex beams carrying orbital angular momentum have potential applications on optical trapping, optical communication with high capacity, quantum information processing. However, the beam quality is degraded in vortex beams generated with spiral phase plates or resonator mirrors with defect spots and optical conversion efficiency in solid-state lasers is sacrificed by controlling the loss of resonator. It is a big challenge for generating high beam quality, high-order cylindrical vector beams with large topological charge in compact solid-state lasers. Here, high-order cylindrical vector beams [Laguerre-Gaussian (LG) modes with zero degree and order of l, LG0,l] with tunable topological charges up to 14 have been generated in an annular beam pumped Yb:YAG microchip laser by manipulating the pump power-dependent population inversion distribution. Efficient performance with optical efficiency of 17.5% has been achieved. The output power is 1.36 W for a vector-vortex laser with 14 topological charges. The pump power dependent wavelength tunable and dual-wavelength laser oscillation in vector-vortex beams has been observed by controlling the reabsorption loss at 1030 nm. Wavelength tunable, dual-wavelength (1030 and 1050 nm) laser oscillation has been achieved for vector-vortex beams with topological charges of 8, 9, and 10. The laser beam quality factor M2 close to the theoretical value (l + 1) has been achieved for LG0,l vector-vortex beams with tunable topological charges up to 14. This work provides a new effective method for generating large topological charge high-order cylindrical vector beams in solid-state microchip lasers with high efficiency and high beam quality.
High-order Laguerre-Gaussian (LG 0,n ) petal-like lasers are extremely important for manipulating microparticles, creating 3D optical trapping structures, and free space optical communication. However, it is difficult to expand the wavelength of LG 0,n petal-like lasers owing to the narrow fluorescence spectrum of laser gain media. Here, a Raman laser constructed with a Yb 3+ :Y 3 Al 5 O 12 (Yb:YAG) crystal and a yttrium vanadate (YVO 4 ) is demonstrated for achieving a high-order LG 0,n petal-like laser with broadband laser wavelength and high beam quality. High-order LG 0,n petal-like lasers with n tunable from 3 to 11 are obtained. The LG 0,11 petal-like Raman laser oscillates from 1075.4 to 1088.7 nm with 44 longitudinal modes, and the bandwidth of the Raman laser is 13.3 nm. The output power of the LG 0,11 petal-like Raman laser is 126 mW with an optical efficiency of 1.5%. High-order LG 0,n petal-like Raman lasers with tunable n provide flexible choices for potential applications in manipulating microparticles and biological molecules.
Optical vortex arrays with multiple singularities arranged in distinct lattice structures provide more flexibility in trapping or manipulating microparticles, large-capacity optical communications and high-security information processing, and optical modulation. An efficient high-power compact laser with singularity-tunable vortex-array distribution is crucial for practical applications. Here, we directly generate various vortex arrays with tunable singularities from 1 to 10 in a microchip laser pumped with a tilted annular beam. Formation of vortex arrays in the microchip laser is achieved by manipulating the gain distribution in an Yb:YAG crystal by controlling the tilt angles and pump power. Efficient high-power laser operation with output power of 2.01 W and optical efficiency of 24.5% is obtained for a vortex array with 10 singularities. The pump-power-dependent saturated population inversion distribution plays a key role in generating vortex arrays formed with multi-transverse modes oscillating simultaneously in transverse-mode locking. The good agreement between theoretically simulated transverse patterns, phases and interference patterns for the vortex arrays and experimentally obtained results provides a solid foundation for developing efficient compact microchip lasers for generating vortex arrays by manipulating gain distribution in a thin medium pumped with a tilted annular beam.
Crisscross vortex arrays have well-defined arrangements of vortices, are ideal light sources for efficiently manipulating multiple microparticles, assemble microprocessing, and optical communications. However, the output power of crisscross vortex arrays is low and laser operating wavelength is limited by the narrow emission spectrum of Nd:YVO 4 crystal.The operating wavelength of optical vortex arrays expands their applications and various methods such as frequency doubling; stimulated Raman scattering (SRS) effect was applied for
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.