Sakkaki Babak, Rasooli Saghai Hassan, Darvish Ghafar, Khatir Mehdi
Department of Electrical and Computer Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Department of Electrical Engineering, Tabriz Branch, Islamic Azad University, Tabriz, Iran.
Beilstein J Nanotechnol. 2020 Jul 15;11:1036-1044. doi: 10.3762/bjnano.11.88. eCollection 2020.
Recent experiments suggest graphene-based materials as candidates in future electronic and optoelectronic devices. In this paper, we propose to investigate new photodetectors based on graphene nanomeshes (GNMs). Density functional theory (DFT) calculations are performed to gain insight into electronic and optical characteristics of various GNM structures. To investigate the device-level properties of GNMs, their current-voltage characteristics are explored by DFT-based tight-binding (DFTB) in combination with non-equilibrium Green's function (NEGF) methods. Band structure analysis shows that GNMs have both metallic and semiconducting properties depending on the arrangements of perforations. Also, absorption spectrum analysis indicates attractive infrared peaks for GNMs with semiconducting characteristics, making them better photodetectors than graphene nanoribbon (GNR)-based alternatives. The results suggest that GNMs can be potentially used in mid-infrared detectors with specific detectivity values that are 100-fold that of graphene-based devices and 1000-fold that of GNR-based devices. Hence, the special properties of graphene combined with the quantum feathers of the perforation makes it suitable for optical devices.
近期实验表明，基于石墨烯的材料有望应用于未来的电子和光电器件。在本文中，我们提议研究基于石墨烯纳米网（GNM）的新型光电探测器。进行密度泛函理论（DFT）计算以深入了解各种GNM结构的电子和光学特性。为了研究GNM的器件级特性，通过基于DFT的紧束缚（DFTB）结合非平衡格林函数（NEGF）方法来探索其电流-电压特性。能带结构分析表明，根据穿孔的排列方式，GNM兼具金属和半导体特性。此外，吸收光谱分析表明，具有半导体特性的GNM具有吸引人的红外峰，使其成为比基于石墨烯纳米带（GNR）的同类产品更好的光电探测器。结果表明，GNM可潜在地用于中红外探测器，其特定探测率是基于石墨烯器件的100倍，基于GNR器件的1000倍。因此，石墨烯的特殊性质与穿孔的量子特性相结合，使其适用于光学器件。
