The excitation of high-order Laguerre–Gaussian（LG） modes in a neodymium-doped yttrium aluminum garnet（Nd:YAG） laser resonator was presented by applying the diffraction of a second-order circular Dammann grating（...The excitation of high-order Laguerre–Gaussian（LG） modes in a neodymium-doped yttrium aluminum garnet（Nd:YAG） laser resonator was presented by applying the diffraction of a second-order circular Dammann grating（CDG） for annular pumping. In the study, the 808 nm pump light was shaped into a double-ring structure by the CDG and matched spatially with that of an ideal LG11 mode. As a result, the laser resonator generated an LG11 vortex mode, and the laser power reached 204 mW with 14.5% slope efficiency. Also, when the cavity mirror was tilted, the laser output could switch to the LG01 vortex mode. The results showed the convenience and versatility of CDG in an annular-pumped vortex laser.展开更多
为了从系统的角度研究大气湍流对涡旋光束传播质量的影响,根据广义惠更斯-菲涅尔积分和Kolmogorov湍流大气原理,利用傅里叶光学分析方法和光束分步传播法对携带有轨道角动量(OAM)的拉盖尔-高斯(LG)光束在湍流大气中的传播进行理论分析...为了从系统的角度研究大气湍流对涡旋光束传播质量的影响,根据广义惠更斯-菲涅尔积分和Kolmogorov湍流大气原理,利用傅里叶光学分析方法和光束分步传播法对携带有轨道角动量(OAM)的拉盖尔-高斯(LG)光束在湍流大气中的传播进行理论分析与数值仿真,导出角谱形式的衍射模型及其对应的抽样限制条件。利用桶中功率(PIB,power in bucket)计算方法,分析湍流强度对不同OAM值的LG光束质量的影响;引入高斯光束和点光源,对比评估典型光束的抗湍流能力。数值仿真结果表明:受大气湍流影响,随着LG光束在湍流大气中传播距离增加,光束会聚能力变弱有明显扩散;光束本身特有的环状光强分布及其相应的相位分布都受到不同程度的破坏,损伤程度与光束本身携带的OAM数有关;点光源对湍流的影响最为敏感;高斯光束具有与小OAM值的LG光束相比拟的抗湍流能力,且比大OAM数的LG光束有更强的抗湍流能力。展开更多
The basic physical characteristics of electrons accelerated by two linearly polarized and circularly symmetric crossed Laguerre-Gaussian （LG） laser beams with equal frequency and amplitude in vacuum are studied in d...The basic physical characteristics of electrons accelerated by two linearly polarized and circularly symmetric crossed Laguerre-Gaussian （LG） laser beams with equal frequency and amplitude in vacuum are studied in detail. The condition, under which electrons can be accelerated effectively, and the energy gain are discussed.展开更多
基金supported by the National Natural Science Foundation of China(No.61475166)
文摘The excitation of high-order Laguerre–Gaussian（LG） modes in a neodymium-doped yttrium aluminum garnet（Nd:YAG） laser resonator was presented by applying the diffraction of a second-order circular Dammann grating（CDG） for annular pumping. In the study, the 808 nm pump light was shaped into a double-ring structure by the CDG and matched spatially with that of an ideal LG11 mode. As a result, the laser resonator generated an LG11 vortex mode, and the laser power reached 204 mW with 14.5% slope efficiency. Also, when the cavity mirror was tilted, the laser output could switch to the LG01 vortex mode. The results showed the convenience and versatility of CDG in an annular-pumped vortex laser.
文摘为了从系统的角度研究大气湍流对涡旋光束传播质量的影响,根据广义惠更斯-菲涅尔积分和Kolmogorov湍流大气原理,利用傅里叶光学分析方法和光束分步传播法对携带有轨道角动量(OAM)的拉盖尔-高斯(LG)光束在湍流大气中的传播进行理论分析与数值仿真,导出角谱形式的衍射模型及其对应的抽样限制条件。利用桶中功率(PIB,power in bucket)计算方法,分析湍流强度对不同OAM值的LG光束质量的影响;引入高斯光束和点光源,对比评估典型光束的抗湍流能力。数值仿真结果表明:受大气湍流影响,随着LG光束在湍流大气中传播距离增加,光束会聚能力变弱有明显扩散;光束本身特有的环状光强分布及其相应的相位分布都受到不同程度的破坏,损伤程度与光束本身携带的OAM数有关;点光源对湍流的影响最为敏感;高斯光束具有与小OAM值的LG光束相比拟的抗湍流能力,且比大OAM数的LG光束有更强的抗湍流能力。
基金Project supported by the National Natural Science Foundation of China （Grant No 10574097）.
文摘The basic physical characteristics of electrons accelerated by two linearly polarized and circularly symmetric crossed Laguerre-Gaussian （LG） laser beams with equal frequency and amplitude in vacuum are studied in detail. The condition, under which electrons can be accelerated effectively, and the energy gain are discussed.
