Electronic structure, optical properties, and lattice dynamics in atomically thin indium selenide flakes  

作　　者：Juan F. Sanchez-Royo Suillermo Munoz-Matutano Mauro Brotons-Gisbert Juan P. Martinez-Pastor Alfredo Segura Andres Cantarero Rafael Mata Josep Canet-Ferrer Gerard Tobias Enric Canadell Jose Marques-Hueso Brian D. Gerardot 

机构地区：[1]ICMUV, Instituto de Oencia de Materiales, Universidad de Valencia, P.O. Box 22085, 46071 Valencia, Spain [2]MALTA-Consolider Team, Institut de Ciencia dels Materials-Dpto. de Fisica Apficada, Universitat de Valencia, E-46100 Burjassot (Valencia), Spain [3]Institut de Ciencia de Materials de Barcelona (ICMAB-CSIC), Campus de la UAB, 08193 Bellaterra, Barcelona, Spain [4]Institute of Photonics and Quantum Science, SUPA, Hefiot-Watt University, Edinburgh EH14 4AS, UK

出　　处：《Nano Research》2014年第10期1556-1568,共13页纳米研究（英文版）

摘　　要：The progressive stacking of chalcogenide single layers gives rise to two- dimensional semiconducting materials with tunable properties that can be exploited for new field-effect transistors and photonic devices. Yet the properties of some members of the chalcogenide family remain unexplored. Indium selenide （InSe） is attractive for applications due to its direct bandgap in the near infrared, controllable p- and n-type doping and high chemical stability. Here, we reveal the lattice dynamics, optical and electronic properties of atomically thin InSe flakes prepared by micromechanical cleavage. Raman active modes stiffen or soften in the flakes depending on which electronic bonds are excited. A progressive blue-shift of the photoluminescence peaks is observed for decreasing flake thickness （as large as 0.2 eV for three single layers）. First-principles calculations predict an even larger increase in the bandgap, 0.40 eV, for three single layers, and as much as 1.1 eV for a single layer. These results are promising from the point of view of the versatility of this material for optoelectronic applications at the nanometer scale and compatible with Si and III-V technologies.chalcogenide 单身者层的进步的叠与能为新地效果晶体管和 photonic 设备被利用的悦耳的性质产生二维的半导体的材料。然而， chalcogenide 家庭的一些成员的性质仍然保持未经勘探。铟硒化物(InSe ) 由于它在近红外线的、可控制的 p 类型并且 n 类型做和高化学稳定性的直接 bandgap 为应用是吸引人的。这里，我们揭示格子动力学，原子地薄的 InSe 薄片的光、电子的性质由 micromechanical 劈开准备了。拉曼活跃模式在取决于电子契约激动的薄片使硬或弄软。一进步光致发光山峰蓝移动为减少的薄片厚度被观察(象为三单个层的 0.2 eV 一样大) 。第一原则的计算在 bandgap 预言甚至更大的增加， 0.40 eV 为三单个层，并且为单个层的差不多 1.1 eV。这些结果与 Si 和 III-V 技术从为在纳米规模和兼容机的 optoelectronic 应用的这材料的通用性的观点是有希望的。

关 键 词：indium selenide two-dimensional flakes micro-Raman spectroscopy MICRO-PHOTOLUMINESCENCE electronic structure 

分 类 号：TN16[电子电信—物理电子学] O613.71[理学—无机化学]