Gong Su-Hyun, Park Q-Han
Opt Express. 2021 Mar 29;29(7):10631-10638. doi: 10.1364/OE.421548.
The transverse nature of light leads to longitudinal optical spin. Here, the unprecedented transverse optical spin of propagating waves and guided modes in a gyroelectric medium is clarified. We identify the propagation modes in a bulk gyroelectric medium and their polarization in terms of optical spin. The anisotropic permittivity of a gyroelectric medium results in two propagation modes, slow and fast, in which the optical spin varies according to the propagation direction. When the magnetization direction of the gyroelectric medium and the propagation direction of the light are not parallel, these modes possess both the longitudinal and transverse components of optical spin. We also confirm that a gyroelectric slab waveguide induces transverse optical spin in the guided light. We investigate the transport behavior of transverse optical spin in a gyroelectric slab using numerical calculations with a modified 3D finite difference time domain method. These new gyroelectric guided modes offer a novel approach to the manipulation of optical spin on a nanoscale.
光的横向性质导致纵向光学自旋。在此，阐明了旋电介质中传播波和导模前所未有的横向光学自旋。我们根据光学自旋确定了块状旋电介质中的传播模式及其偏振。旋电介质的各向异性介电常数导致两种传播模式，即慢模式和快模式，其中光学自旋根据传播方向而变化。当旋电介质的磁化方向与光的传播方向不平行时，这些模式同时具有光学自旋的纵向和横向分量。我们还证实，旋电平板波导会在导光中诱导横向光学自旋。我们使用改进的三维有限差分时域方法通过数值计算研究了旋电平板中横向光学自旋的输运行为。这些新的旋电导模为纳米尺度上光学自旋的操控提供了一种新颖的方法。
