论文标题
根据大小和形状优化来调整石墨烯纳米瓦斯的光电响应
Tailoring the opto-electronic response of graphene nanoflakes by size and shape optimization
论文作者
论文摘要
石墨烯的长自旋扩散长度，旋转时间和出色的光吸收系数为构建光电设备以及基于自旋的逻辑提供了一个绝佳的平台。在这项研究中，通过采用密度功能理论及其时间依赖性版本，我们提供了如何使用石墨烯纳米叶片的大小和形状来改变其磁性结构和光学特性的详细分析。由于已知锯齿石石墨烯纳米纤维的边缘在抗铁磁性上对齐，并且扶手椅纳米骨通常是非磁性的，因此两者在纳米瓦器几何形状中的组合可以使用，可用于优化基地磁性结构，并量身定制脱离质量的范围，以使其具有挑战性的范围，以替代范围，以抗抗或抗或抗抗性的效果，切换磁性排序所需的外场。最重要的是，我们表明磁态改变了薄片的光学响应，从而导致了光链应用的可能性。
The long spin-diffusion length, spin-lifetimes and excellent optical absorption coefficient of graphene provide an excellent platform for building opto-electronic devices as well as spin-based logic in a nanometer regime. In this study, by employing density functional theory and its time-dependent version, we provide a detailed analysis of how the size and shape of graphene nanoflakes can be used to alter their magnetic structure and optical properties. As the edges of zigzag graphene nanoribbons are known to align anti-ferromagnetically and armchair nanoribbons are typically non-magnetic, a combination of both in a nanoflake geometry can be used to optimize the ground-state magnetic structure and tailor the exchange coupling decisive for ferro- or anti-ferromagnetic edge magnetism, thereby offering the possibility to optimize the external fields needed to switch magnetic ordering. Most importantly, we show that the magnetic state alters the optical response of the flake leading to the possibility of opto-spintronic applications.
