Pei Yumiao, Hu Yi, Lou Cibo, Song Daohong, Tang Liqin, Xu Jingjun, Chen Zhigang
Opt Lett. 2018 Jan 1;43(1):118-121. doi: 10.1364/OL.43.000118.
We experimentally and theoretically demonstrate a spatial diametric drive acceleration of two mutually incoherent optical beams in 1D optical lattices under a self-defocusing nonlinearity. The two beams, exciting the modes at the top/bottom edges of the first Bloch band and hence experiencing normal/anomalous diffraction, can bind together and bend in the same direction during nonlinear propagation, analogous to the interplay between two objects with opposite signs of mass that breaks Newton's third law. Their spatial spectrum changes associated with the acceleration are analyzed for different lattice modulations. We find that the acceleration limit is determined by the beam exciting the top band edge that reaches a saturated momentum change prior to the other pairing beam.
我们通过实验和理论证明，在自散焦非线性下的一维光学晶格中，两束相互非相干的光束会出现空间直径驱动加速现象。这两束光激发第一布洛赫带顶部/底部边缘的模式，从而经历正常/反常衍射，在非线性传播过程中它们可以结合在一起并沿相同方向弯曲，类似于质量符号相反的两个物体之间的相互作用，这种相互作用打破了牛顿第三定律。针对不同的晶格调制，分析了与加速相关的它们的空间频谱变化。我们发现，加速极限由激发顶部能带边缘的光束决定，该光束在另一对配对光束之前达到饱和动量变化。
