论文标题
与时空编码数字跨表面的超螺旋时变oAM光束
Generation of superhelical time-varying OAM beam with space-time-coding digital metasurface
论文作者
论文摘要
最近提出的具有高谐波生成（HHG）实现的时变轨道角动量（OAM）的极端脉冲梁（EUV）梁为量子激发控制和颗粒操作提供了非凡的工具。但是，这种方法不容易可扩展到其他频率制度。在这里，我们设计了一个以微波频率运行的时空编码数字跨表面，以实验生成不同的时间变化的OAM模式。我们还介绍了具有随时间变化的OAM的超螺旋性的概念，并具有波前结构的高阶扭曲，可以通过元图的时间非线性来进一步实现，这可以进一步实现。通过开发两种探针测量技术，我们在时间上动态绘制了OAM场模式。提出的超螺旋时变oam梁为粒子操作和OAM多路复用通信铺平了一种方式。
The recently proposed extreme-ultraviolet (EUV) beams with time-varying orbital angular momentum (OAM) realized by high-harmonic generation (HHG) provides extraordinary tools for quantum excitation control and particle manipulation. However, such an approach is not easily scalable to other frequency regimes. Here, we design a space-time-coding digital metasurface operating in microwave frequencies to experimentally generate different modes of time-varying OAM. We also introduce a concept of superhelicity of time-varying OAM with a higher-order twist of the wavefront structure, which can be further realized by reflection phase profiles nonlinear in time through the metasurface. By developing a two-probe measurement technique, we dynamically map the OAM field pattern varying in time. The proposed superhelical time-varying OAM beam paves a way for particle manipulations and OAM multiplexing communications.
