Observation of valley-dependent beams in photonic graphene
Observation of valley-dependent beams in photonic graphene
复制标题
光子石墨烯中谷相关光束的观察
DOI：
10.1364/oe.22.023605
复制
发表时间：
2014-09-22
期刊：
影响因子：
3.8
通讯作者：
Chen, Hong
中科院分区：
文献类型：
--
作者：
Deng, Fusheng;Sun, Yong;Chen, Hong
研究了在微波波段下，类似于石墨烯中电子的人工光子六角晶格中光的谷相关传播。数值计算和实验结果表明，当频率远离狄拉克点时，光子石墨烯的谷简并被打破。利用等值线分析了由于不同的谷而引起的特殊的各向异性波输运性质。更有趣的是，谷依赖的自准直和光束分裂现象的实验证明与扶手椅和锯齿形界面，分别。我们的研究结果证实了在光子石墨烯中存在两个不等价的Dirac点，导致两个不同的谷，这两个谷可以用来控制光的流动，并且可以用来在谷偏振分束器、准直器或导向装置中携带信息。(C)2014年美国光学学会
Valley-dependent propagation of light in an artificial photonic hexagonal lattice, akin to electrons in graphene, is investigated in microwave regime. Both numerical and experimental results show that the valley degeneracy in the photonic graphene is broken when the frequency is away from the Dirac point. The peculiar anisotropic wave transport property due to distinct valleys is analyzed using the equifrequency contours. More interestingly, the valley-dependent self-collimation and beam splitting phenomena are experimentally demonstrated with the armchair and zigzag interfaces, respectively. Our results confirm that there are two inequivalent Dirac points that lead to two distinct valleys in photonic graphene, which could be used to control the flow of light and might be used to carry information in valley polarized beam splitter, collimator or guiding device. (C) 2014 Optical Society of America