Direct generation of 3.17 mJ green pulses in a cavity-dumped Ho^(3+)-doped fiber laser at 543 nm

High-energy pulsed lasers in the green spectral region are of tremendous interest for applications in space laser ranging,underwater detection,precise processing,and scientific research.Semiconductor pulsed lasers currently are difficult to access to the so-called“green gap,”and high-energy green pulsed lasers still heavily rely on the nonlinear frequency conversion of near-IR lasers,precluding compact and low-cost green laser systems.Here,we address this challenge by demonstrating,for the first time to the best of our knowledge,millijoule-level green pulses generated directly from a fiber laser.The green pulsed fiber laser consists of a 450 nm pump laser diode,a Ho^(3+)-doped ZBLAN fiber,and a cavity-dumping module based on a visible wavelength acousto-optic modulator.Stable pulse operation in the cavity-dumping regime at 543 nm is observed with a tunable repetition rate in a large range of 100 Hz–3 MHz and a pulse duration of 72–116 ns.The maximum pulse energy of 3.17 mJ at 100 Hz is successfully achieved,which is three orders of magnitude higher than those of the rare-earth-doped fiber green lasers previously reported.This work provides a model for compact,high-efficiency,and high-energy visible fiber pulsed lasers.

3.6 W compact all-fiber Pr3+-doped green laser at 521 nm

Green semiconductor lasers are still undeveloped,so high-power green lasers have heavily relied on nonlinear frequency conversion of near-infrared lasers,precluding compact and low-cost green laser systems.Here,we report the first Watt-level all-fiber CW Pr3t-doped laser operating directly in the green spectral region,addressing the aforementioned difficulties.The compact all-fiber laser consists of a double-clad Pr3t-doped fluoride fiber,two homemade fiber dichroic mirrors at visible wavelengths,and a 443-nm fiber-pigtailed pump source.Benefitting from>10 MW∕cm2 high damage intensity of our designed fiber dielectric mirror,the green laser can stably deliver 3.62-W of continuous-wave power at∼521 nm with a slope efficiency of 20.9%.To the best of our knowledge,this is the largest output power directly from green fiber lasers,which is one order higher than previously reported.Moreover,these green all-fiber laser designs are optimized by using experiments and numerical simulations.Numerical results are in excellent agreement with our experimental results and show that the optimal gain fiber length,output mirror reflectivity,and doping level should be considered to obtain higher power and efficiency.This work may pave a path toward compact high-power green all-fiber lasers for applications in biomedicine,laser display,underwater detection,and spectroscopy.