Precise control of positive and negative Goos-Hanchen shifts in graphene
Precise control of positive and negative Goos-Hanchen shifts in graphene
复制标题
精确控制石墨烯的正负古斯汉欣位移
DOI：
10.1016/j.carbon.2019.04.064
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发表时间：
2019-08-01
期刊：
影响因子：
10.9
通讯作者：
Luo, Zhaoming
中科院分区：
文献类型：
--
作者：
Zhou, Xiang;Liu, Shuoqing;Luo, Zhaoming
我们利用转移矩阵方法全面研究了石墨烯-基底体系中的古斯-汉欣（GH）效应。结果表明，在衬底折射率固定的情况下，GH位移的大小和符号与石墨烯电导率的虚部密切相关，而布儒斯特角位置很大程度上受电导率实部的影响。进一步的研究表明，当费米能量超过0.4 eV时，布儒斯特角的位置保持不变，并且在一定布儒斯特角处GH位移的大小和符号仅受费米能量的影响。在此基础上，提出了一种精确控制GH正负变化的方案并通过实例进行了论证。我们首先在费米能量超过0.4 eV的情况下调节衬底的折射率来控制布儒斯特角位置，然后调节费米能量使GH位移接近目标值。最后，我们应用GH位移的这些精确控制特性来设计具有可调灵敏度系数的折射率检测器。这些研究可能在高灵敏度、精确测量石墨烯参数的折射率传感器中具有潜在的应用前景。 (C) 2019 Elsevier Ltd. 保留所有权利。
We study the Goos-Hanchen (GH) effect in a graphene-substrate system comprehensively by using the transfer matrix method. It is revealed that the magnitude and sign of GH shifts are closely related to the imaginary part of graphene conductivity in the case of the fixed refractive index of substrate, while the Brewster angle position is largely influenced by the real part of conductivity. Further studies show that the position of Brewster angle keeps invariable when the Fermi energy exceeds 0.4 eV, and the magnitude and sign of GH shifts at a certain Brewster angle are changed only by Fermi energy. On the basis of these findings, a scheme to control the positive and negative GH shifts precisely is proposed and demonstrated by instances. We first adjust the refractive index of substrate to control the Brewster angle position under the condition of the Fermi energy exceeding 0.4 eV, and then adjust the Fermi energy to make the GH shift approach target value. Finally, we apply these precise control properties of GH shift to design a refractive index detector with adjustable sensitivity coefficient. These researches may have potential applications in refractive index sensor with high sensitivity and precise measurement of graphene parameters. (C) 2019 Elsevier Ltd. All rights reserved.