标题： 二次准相位匹配光子晶体中的手性孤子 显示英文标题

标题： Chiral solitons in quadratic quasi-phase-matched photonic crystals

摘要： 我们在二次非线性晶体中引入了一种准相位匹配技术，通过改变条纹的倾斜角度构造出一种人工规范场，这通过晶体沿非线性极化率的正负方向实现。 与其他设置中通过线性耦合构建的人工规范场不同，该系统中的规范场是通过非线性耦合实现的。 我们证明这种规范场可以产生具有螺旋能量流并围绕孤子旋转的稳定手性孤子。 与使用相同种类或频率产生的传统手性电流相比，本系统中的手性电流是由基频和二次谐波成分之间的相互耦合形成的。 我们推导了该系统中手性能量流的半解析解。 发现存在一个最优的倾斜角度，在不同参数下可以最大化手性能量流，且这个最优倾斜角度与功率和失谐呈正相关。 还讨论了手性孤子的迁移性和碰撞。 结果表明，手性孤子会对外部扰动作出响应，并且彼此之间发生完全弹性的碰撞。 此外，还概述了实验生成手性孤子和手性电流的可能性。 显示英文摘要

摘要： We introduce a quasi-phase-matched technique in quadratic nonlinear crystals, constructing an artificial gauge field by changing the inclination angle of stripes, which is realized by the positive and negative polarization directions of nonlinear susceptibility along the crystal. Unlike the artificial gauge field constructed through linear coupling in other settings, the gauge field in this system is realized by nonlinear coupling. We demonstrate that this gauge field can generate stable chiral solitons with chiral energy flow rotating around the solitons. In contrast to conventional chiral currents generated with the same specie or frequency, the chiral currents in the present system are formed by mutual coupling between fundamental frequency and second harmonic components. We derive the semi-analytical solution for the chiral energy flow in this system. It is found that there exists an optimal inclination angle that can maximize the chiral energy flow under different parameters, and this optimal inclination shows a positive correlation with the power and detuning. The mobility and collisions of the chiral solitons are also discussed. The results show that chiral solitons move in response to kicking and undergo fully elastic collisions with each other. In addition, the possibility of experimentally generating chiral solitons and chiral currents is outlined.