Author Affiliations
1School of Science and Technology, Jiangxi Normal University, Nanchang 330022, China2State Key Laboratory of Advanced Optical Communication Systems and Networks, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China3Jiangxi Key Laboratory of Photoelectronics and Telecommunication, Department of Physics, Jiangxi Normal University, Nanchang 330022, China4Collaborative Innovation Center of Light Manipulations and Applications, Shandong Normal University, Jinan 250358, Chinashow less
Fig. 1. Schematic of the experimental setup. HWP, half-wave plate; G-T prism, Glan–Taylor prism; L1–L4, lens with the focal length of 50, 100, 200, and 50 mm, respectively; medium, 5% (mole fraction) magnesium-oxide-doped periodically poled lithium niobate (MgO:PPLN); F, filter; S, screen.
Fig. 2. Generation of the SH vortex patterns carrying different l2, where l2 = 2l1, and l1 is the TC of the structured FW. The first row is the phase masks of the FW beams with different TCs for (a1) l1 = 1, (a2) l1 = 2, (a3) l1 = 3, (a4) l1 = 2.5, (a5) l1 = 2.7, and (a6) l1 = 2.9, respectively. The second and third rows show the corresponding simulation and experimental intensity profiles of the SH vortex with different TCs for (c1) l2 = 2, (c2) l2 = 4, (c3) l2 = 6, (c4) l2 = 5, (c5) l2 = 5.4, and (c6) l2 = 5.8, respectively. In this case, the obliquity factor is constant (a = 1).
Fig. 3. Intensity patterns of the SH vortices with different obliquity factors. The first row denotes the phase profiles of the FW beams with different obliquity factors for (a1) a = 1, (a2) a = 2, (a3) a = 4, (a4) a = 0.5, (a5) a = 1.5, and (a6) a = 4.5, respectively. The TC l1 = 2 is fixed in this case. The simulation and experimental intensity patterns of the SH wave are arranged and displayed in the second and the third rows, respectively.
Fig. 4. Experimental comparison on the intensity patterns of generated SH waves by switching the sign of the TC of the structured FW beam and the obliquity factor, respectively. (a)–(d) Corresponding to cases of input OAM and obliquity factors that are l1 = +2, a = 3, l1 = −2, a = 3, l1 = 1, a = +2, and l1 = 1, a = −2, respectively. The insets are the corresponding simulation of SH vortex beams. The experiments are in good agreement with the simulations.
Fig. 5. Conversion efficiency of SH waves pumped by different OAM states with the fixed obliquity factor a = 1.