论文标题
可调电子特性和电场诱导的磷酸/石墨烯异质结构中的相变
Tunable electronic properties and electric-field-induced phase transition in phosphorene/graphene heterostructures
论文作者
论文摘要
单一组件系统的缺点，例如石墨烯的无间隙性质，缺乏磷烯等的空气稳定性等等，引起了人们对预期表现出有趣的电子和光学特性的堆叠材料的极大关注。使用紧密结合方法和绿色的功能方法，我们研究了扶手椅边缘侧磷烯/石墨烯异质结构的电子特性，它们是半导体/半导体或半导体/金属异质结构，取决于石墨烯色带的宽度。发现系统是狭窄的，可以通过调整域的大小来调制带隙。此外，对磷酸成分磷酸宽度的带隙变化的分析表明，在半导体/金属异质结构中，磷烯色带不会在费米水平附近诱导任何电子状态，这表明应将抑制的电子传输归因于跨界面的孔传递。此外，我们表明横向电场可以显着多样化异质结构的电子行为，即异质结构经历半导体 - 金属相变。此外，调整横向电场会产生一种有趣的可能性，即系统可以经历从带绝缘子到拓扑绝缘体的拓扑相变。
The shortcomings of mono-component systems, e.g., the gapless nature of graphene, the lack of air-stability in phosphorene, etc. have drawn great attention toward stacked materials expected to show interesting electronic and optical properties. Using the tight-binding approach and the Green's function method, we investigate the electronic properties of armchair-edged lateral phosphorene/graphene heterostructures, which are either semiconductor/semiconductor or semiconductor/metal heterostructures, depending on the width of graphene ribbon. It is found that the system is narrow-gapped, and the bandgap can be modulated by tuning the size of the domains. Besides, the analysis of the bandgap variation against the width of the component phosphorene ribbon indicates that, in semiconductor/metal heterostructure, phosphorene ribbon does not induce any electronic state near the Fermi level, suggesting that the suppressed electron transport should be attributed to the hole transfer across the interface. Furthermore, we show that the transverse electric field can significantly diversify the electronic behavior of the heterostructure, i.e., the heterostructure undergoes the semiconductor-metal phase transition. Moreover, tuning the transverse electric field yields an intriguing possibility that the system can undergo a topological phase transition from a band insulator to a topological insulator.
