Li Yun, Li Xiaobo, Zhang Shidong, Cao Liemao, Ouyang Fangping, Long Mengqiu
Hunan Key Laboratory of Super Micro-structure and Ultrafast Process, School of Physics and Electronics, Central South University, Changsha, 410083, China.
Department of Applied Physics, Hunan University of Technology and Business, Changsha, 410205, China.
Nanoscale Res Lett. 2021 Jan 6;16(1):5. doi: 10.1186/s11671-020-03461-3.
Strain engineering has become one of the effective methods to tune the electronic structures of materials, which can be introduced into the molecular junction to induce some unique physical effects. The various γ-graphyne nanoribbons (γ-GYNRs) embedded between gold (Au) electrodes with strain controlling have been designed, involving the calculation of the spin-dependent transport properties by employing the density functional theory. Our calculated results exhibit that the presence of strain has a great effect on transport properties of molecular junctions, which can obviously enhance the coupling between the γ-GYNR and Au electrodes. We find that the current flowing through the strained nanojunction is larger than that of the unstrained one. What is more, the length and strained shape of the γ-GYNR serves as the important factors which affect the transport properties of molecular junctions. Simultaneously, the phenomenon of spin-splitting occurs after introducing strain into nanojunction, implying that strain engineering may be a new means to regulate the electron spin. Our work can provide theoretical basis for designing of high performance graphyne-based devices in the future.
应变工程已成为调节材料电子结构的有效方法之一，可引入分子结以诱导一些独特的物理效应。设计了各种在应变控制下嵌入金（Au）电极之间的γ-石墨炔纳米带（γ-GYNRs），包括通过采用密度泛函理论计算自旋相关的输运性质。我们的计算结果表明，应变的存在对分子结的输运性质有很大影响，它可以显著增强γ-GYNR与Au电极之间的耦合。我们发现，流过应变纳米结的电流大于未应变纳米结的电流。此外，γ-GYNR的长度和应变形状是影响分子结输运性质的重要因素。同时，在纳米结中引入应变后会出现自旋分裂现象，这意味着应变工程可能是调节电子自旋的一种新手段。我们的工作可为未来高性能石墨炔基器件的设计提供理论依据。
