论文标题
第四阶特殊点附近的异国光动力学
Exotic light dynamics around a fourth order exceptional point
论文作者
论文摘要
特殊点（EP）奇异性的物理学一直是开放系统中广泛独特的物理应用的关键。在这种情况下，物理系统中四阶EP（EP4）周围四个耦合状态之间的相互作用尚未探索。在这里，我们根据仅基于两个可调参数的多层增益型剖面，研究了具有多层增益损失的可行平面光学波导中EP4的独特特征。由于EP4周围的准静态增益变化，已探索了独特的“四阶$β$交换”现象。首次报道了随着增益损失曲线的动态变化的独家手性光动力学，这是一种特殊类型的不对称高阶模式转换方案。在这里，基于包围方向的选择，与EP4关联的所有耦合模式都完全转换为不同的特定高阶模式。提出的方案将EP4作为集成光子设备的新的光操纵工具。
The physics of exceptional point (EP) singularities, has been a key to a wide range of unique physical applications in open systems. In this context, the mutual interactions among four coupled states around a fourth-order EP (EP4) in a physical system is yet to be explored. Here, we investigate the unique features of an EP4 in a fabrication feasible planar optical waveguide with a multilayer gain-loss profile based on only two tunable parameters. A unique `fourth-order $β$-switching' phenomenon due to quasi-static gain-loss variation around EP4 has been explored. An exclusive chiral light dynamics following the dynamical variation of the gain-loss profile has been reported for the first time, which enables a special type of asymmetric higher-order mode conversion scheme. Here, all the coupled modes associated with an EP4 are fully converted into different specific higher-order modes based on the choice of encirclement directions. The proposed scheme would present EP4 as a new light manipulation tool for integrated photonic devices.
