We report the direct generation of optical vortex arrays in a diode-pumped bulk Yb:CALGO laser. By adjusting the angles of the input mirror, output coupler and laser crystal to achieve off-axis-pumped condition, the ring-shaped LG0,±1, two to six order vortex array have been obtained. The phase singularities of optical vortex arrays were tunable from 1 to 6. When the pump power was 13.41 W, the maximum output power of LG0,±1, double-vortex array, three-vortex array and four-vortex array were 1.93 W, 1.5 W, 1.02 W and 0.79 W respectively. The chirality could be adjusted by rotating the output coupler. The topological charges of each phase singularity were determined by interference pattern. Theoretical simulation including intensity distribution, interference fringes and phase distribution have been analyzed. The simulations are in good accordance with experimental results.

No abstract

No abstract

We present a high-power, wavelength-tunable picosecond Yb3+: CaGdAlO4 (Yb:CALGO) laser based on MgO-doped lithium niobate (MgO:LN) nonlinear mirror mode locking. The output wavelength in the continuous wave (CW) regime is tunable over a 45 nm broad range. Mode locking with a MgO:LN nonlinear mirror, the picosecond laser is tunable over 23 nm from 1039 to 1062 nm. The maximum output power of the mode-locked laser reaches 1.46 W, and the slope efficiency is 18.6%. The output pulse duration at 1049 nm is 8 ps. The laser repetition rate and bandwidth are 115.5 MHz and 1.7 nm, respectively.

No abstract