Optical spectroscopy of graphene: From the far infrared to the ultraviolet
Optical spectroscopy of graphene: From the far infrared to the ultraviolet
复制标题
DOI：
10.1016/j.ssc.2012.04.064
复制
发表时间：
2012-08-01
影响因子：
2.1
通讯作者：
Heinz, Tony F.
中科院分区：
文献类型：
--
作者：
Mak, Kin Fai;Ju, Long;Heinz, Tony F.
石墨烯独特的电子结构导致了几种独特的光学性质。在这篇简短的综述中，我们概述了目前对石墨烯光学响应的两个一般方面的理解：光吸收和光发射。我们发现，石墨烯的光吸收主要是在低光子能量（在远红外光谱范围内）和带间跃迁在较高的能量（从中红外到紫外）的带内跃迁。我们讨论了如何在石墨烯带内和带间跃迁可以通过静电门修改。我们描述了从自由载流子（带内）响应和激子效应所产生的等离子体共振，表现在带间吸收。由于没有带隙，石墨烯中的光发射（吸收的逆过程）很弱。我们表明，从热电子的光致发光，但是，可以通过飞秒激光激发或强静电门成为可观察的。(c)2012爱思唯尔有限公司保留所有权利。
The unique electronic structure of graphene leads to several distinctive optical properties. In this brief review, we outline the current understanding of two general aspects of optical response of graphene: optical absorption and light emission. We show that optical absorption in graphene is dominated by intraband transitions at low photon energies (in the far-infrared spectral range) and by interband transitions at higher energies (from mid-infrared to ultraviolet). We discuss how the intraband and interband transitions in graphene can be modified through electrostatic gating. We describe plasmonic resonances arising from the free-carrier (intraband) response and excitonic effects that are manifested in the interband absorption. Light emission, the reverse process of absorption, is weak in graphene due to the absence of a band gap. We show that photoluminescence from hot electrons can, however, become observable either through femtosecond laser excitation or strong electrostatic gating. (c) 2012 Elsevier Ltd. All rights reserved.