Chinese Optics Letters, 2015, 13 (3): 031405, Published Online: Sep. 25, 2018
Simple Nd:YAG laser generates vector and vortex beam Download: 1141次
140.3580 Lasers, solid-state 140.3540 Lasers, Q-switched 140.3530 Lasers, neodymium 140.3480 Lasers, diode-pumped 140.3410 Laser resonators
Abstract
We report a simple Nd:YAG laser that emits radially polarized beam with helical wavefront. The laser cavity consists of a piece of laser crystal and a plane output coupler, and there is no additional polarization component inside it. The pump light is converted into annular profile through de-focal coupling into a multi-mode fiber. For the continuous-wave (CW) operation, the laser emits radially polarized vortex beam, and it is observed that the helical wavefront of the laser beam is switched from right handedness to left handedness when the output coupler is tilted slightly. For the Q -switched operation under the insertion of a Cr 4 + : YAG saturable absorber inside the cavity, we obtain radially polarized outputs with left-handedness helical wavefront. By tilting the laser crystal slightly, the laser output switches to azimuthal polarization at pump power larger than 4.5 W and left-handedness helical wavefront of laser beam is preserved.
Zhiqiang Fang, Yao Yao, Kegui Xia, Jianlang Li. Simple Nd:YAG laser generates vector and vortex beam[J]. Chinese Optics Letters, 2015, 13(3): 031405.