Akulshin Alexander M, Novikova Irina, Mikhailov Eugeniy E, Suslov Sergey A, McLean Russell J
Opt Lett. 2016 Mar 15;41(6):1146-9. doi: 10.1364/OL.41.001146.
We report on experimentally observed addition, subtraction, and cancellation of orbital angular momentum (OAM) in the process of parametric four-wave mixing that results in frequency up- and down-converted emission in Rb vapor. Specific features of OAM transfer from resonant laser fields with different optical topological charges to the spatially and temporally coherent blue light (CBL) have been considered. We have observed the conservation of OAM in nonlinear wave mixing in a wide range of experimental conditions, including a noncollinear geometry of the applied laser beams, and furthermore, that the CBL accumulates the total OAM of the applied laser light. Spectral and power dependences of vortex and plane wavefront blue light beams have been compared.
我们报告了在铷蒸汽中参量四波混频过程中轨道角动量（OAM）的实验观测到的相加、相减和抵消情况，该过程导致频率上转换和下转换发射。已经考虑了从具有不同光学拓扑电荷的共振激光场到空间和时间相干蓝光（CBL）的OAM转移的具体特征。我们在包括所施加激光束的非共线几何结构在内的广泛实验条件下，观测到了非线性波混频中OAM的守恒，此外，CBL积累了所施加激光的总OAM。比较了涡旋和平平面波前蓝光光束的光谱和功率依赖性。
