When light interacts with matter, dichroism with respect to the handedness of circularly polarized light is well established. But what happens if the light further possesses an orbital angular momentum? In this paper, we discuss possible definitions of orbital angular momentum dichroism and define a new type of dichroism, the class dichroism. By numerically calculating the scattering cross-section spectra, we study the dichroism of a plasmonic nanostructure interacting with orbital angular momentum light. By considering the exemplary case of twisted, stacked nanorods, we show that the orbital angular momentum dichroism can be as strong as dichroism induced by circular polarization. We present a detailed classification of the different types of orbital angular momentum dichroism, which paves the way for new chiroptic spectroscopic techniques.

当光与物质相互作用时，关于圆偏振光的旋向性的二向色性得到很好的确立。但是，如果光还具有轨道角动量，会发生什么呢？在本文中，我们讨论了轨道角动量二向色性的可能定义，并定义了一种新型的二向色性，即类二向色性。通过数值计算散射截面光谱，我们研究了与轨道角动量光相互作用的等离子体纳米结构的二向色性。通过考虑扭曲的，堆叠的纳米棒的示例性情况，我们表明，轨道角动量二向色性可以与圆极化引起的二向色性一样强。我们介绍了不同类型的轨道角动量二向色性的详细分类，这为新的按摩光谱技术铺平了道路。