光子石墨烯中赝磁场作用下的谷霍尔效应

将石墨烯中赝磁场的产生机理运用于光子石墨烯,通过在光子石墨烯中引入晶格有规律单轴形变的方式,理论分析得到了谷依赖的均匀赝磁场,并通过数值模拟的方法观察到明显的谷霍尔效应.这种谷霍尔效应的显著程度随晶格形变度的增加而加强.在具有一定损耗的电介质材料构成的形变光子石墨烯中仍可观察到明显的谷霍尔效应.随着电介质材料损耗的增加,谷霍尔效应导致的波束转弯效果依然能够保持,只是强度逐渐变弱.类似于自旋电子学中的自旋霍尔效应,这种光子石墨烯中等效赝磁场作用下的谷霍尔效应在未来谷极化器件的设计和应用中具有重要意义.

Valley Hall effect induced by pseudomagnetic field in distorted photonic graphene

Like the spin in spintronics, the valley index in graphene can be viewed as a new carrier of information, which is useful for designing modern electronic devices. Recently, we have applied the concept of valleytronics to photonic graphene, revealed valley-dependent beam splitting effect and realized pseudomagnetic field. The pseudomagnetic field enables a novel manipulation of photons. In this paper, the photonic analogy of valley Hall effect in uniaxially distorted photonic graphene is investigated. It is found that photons in two valleys are subjected to pseudomagnetic fields that are equal in strength but opposite in sign. With the increasing of distortion, the valley Hall effect becomes stronger. In addition, it is found that the photonic valley Hall effect can still be maintained under the influence of loss, although the beam intensity decreases. The photonic analogy of valley Hall effect induced by pseudomagnetic field in uniaxially distorted photonic graphene may be very useful for controlling the flow of light in future valley-polarized devices.