论文标题
双轴晶体与轨道角动量中锥形衍射产生的涡流的演变
Evolution of vortices created by conical diffraction in biaxial crystals versus orbital angular momentum
论文作者
论文摘要
在通过双轴晶体发生的锥形衍射过程中，已经分析了光态进化与其分数轨道角动量（OAM）。实验结果由kgd的非脱位级联（WO $ _2 $）$ _ 4 $和BI $ _2 $ ZNOB $ _2 $ o $ _6 $ biathxial Crystals提供。连续的$ 0 \至1 \至2 $ $ \ hbar $/光子在通过整数值中的分数OAM增加的增加是在BI $ _2 $ Znob $ _2 $ _2 $ _2 $ o $ o $ _6 $ Crystal的旋转轨道耦合的帮助下操作的。状态光及其涡流的相通过带有参考光束的干扰模式可视化。分数OAM值的演变伴随着一对具有相反符号的涡流对，并与$-π/+π$不连续的相线相连。观察到半耗时OAM周围的相模式演变是连续的。在其他情况下，可以通过破坏$-π/+π$不连续的相线和一对具有相反电荷的新涡流来中断进化。
Light states evolution versus their fractional orbital angular momentum (OAM) has been analyzed in the conical diffraction process occurring through biaxial crystals. Experimental results are provided by a non-degenerate cascade of KGd(WO$_2$)$_4$ and Bi$_2$ZnOB$_2$O$_6$ biaxial crystals. The continuous $0\to 1\to 2$ $\hbar$/photon increasing of the fractional OAM in passing through integer values was operated with the help of the spin-orbit coupling in the Bi$_2$ZnOB$_2$O$_6$ crystal. The phase of the state light and its vortices were visualized by interference patterns with a reference beam. The evolution of the fractional OAM value is accompanied by a continuous evolution of pairs of vortices with opposite signs and linked by a $-π/+π$ discontinuous phase line. The phase pattern evolution around half-integer OAM is observed to be continuous. In other cases, the evolution can be interrupted by the breaking of a $-π/+π$ discontinuous phase line and a new pair of vortices with opposite charges is born.
