Liu Guohua, Zhang Xiliang, Zhang Xin, Hu Yanwen, Li Zhen, Chen Zhenqiang, Fu Shenhe
Department of Optoelectronic Engineering, Jinan University, Guangzhou, 510632, China.
Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Guangzhou, 510632, China.
Light Sci Appl. 2023 Aug 28;12(1):205. doi: 10.1038/s41377-023-01238-8.
Rabi oscillation has been proven to be one of the cornerstones of quantum mechanics, triggering substantial investigations in different disciplines and various important applications both in the classical and quantum regimes. So far, two independent classes of wave states in the Rabi oscillations have been revealed as spin waves and orbital waves, while a Rabi wave state simultaneously merging the spin and orbital angular momentum has remained elusive. Here we report on the experimental and theoretical observation and control of spin-orbit-coupled Rabi oscillations in the higher-order regime of light. We constitute a pseudo spin-1/2 formalism and optically synthesize a magnetization vector through light-crystal interaction. We observe simultaneous oscillations of these ingredients in weak and strong coupling regimes, which are effectively controlled by a beam-dependent synthetic magnetic field. We introduce an electrically tunable platform, allowing fine control of transition between different oscillatory modes, resulting in an emission of orbital-angular-momentum beams with tunable topological structures. Our results constitute a general framework to explore spin-orbit couplings in the higher-order regime, offering routes to manipulating the spin and orbital angular momentum in three and four dimensions. The close analogy with the Pauli equation in quantum mechanics, nonlinear optics, etc., implies that the demonstrated concept can be readily generalized to different disciplines.
拉比振荡已被证明是量子力学的基石之一，引发了不同学科的大量研究以及经典和量子领域的各种重要应用。到目前为止，拉比振荡中的两类独立波态已被揭示为自旋波和轨道波，而同时合并自旋和轨道角动量的拉比波态仍然难以捉摸。在这里，我们报告了在高阶光场中自旋 - 轨道耦合拉比振荡的实验和理论观测及控制。我们构建了一个伪自旋 - 1/2 形式体系，并通过光 - 晶体相互作用光学合成一个磁化矢量。我们在弱耦合和强耦合区域观察到这些成分的同时振荡，它们由与光束相关的合成磁场有效控制。我们引入了一个电可调平台，允许对不同振荡模式之间的转变进行精细控制，从而产生具有可调拓扑结构的轨道角动量光束发射。我们的结果构成了一个探索高阶区域自旋 - 轨道耦合的通用框架，提供了在三维和四维中操纵自旋和轨道角动量的途径。与量子力学、非线性光学等中的泡利方程的紧密类比意味着所展示的概念可以很容易地推广到不同学科。
