论文标题
光照射下垂直异质结构的运输特性
Transport properties of vertical heterostructures under light irradiation
论文作者
论文摘要
光照射下双层异质结构的电子和传输性能是提高光电设备功能的基本兴趣。从理论上讲，我们在时间周期性的外部光场下研究双层石墨烯和双层异质结构的转运性质的修饰。通过使用非平衡绿色的功能形式主义，以陆路类型的配置研究了批量电子和传输性能。为了说明在光照射下双层接触的差分电导的行为，我们考虑了双层石墨烯和石墨烯/六角硼硝酸异质结构的紧密结合模型。非绝热驾驶会引起原始带结构的边带，并在准谱系中的间隙打开。在运输特性中，间隙开口表现为抑制差分电导。除了抑制外，如果光激发电子隧道进入或从Van〜hove奇异性中，外部光场还会引起差分电导的增强。
Electronic and transport properties of bilayer heterostructure under light irradiation are of fundamental interest to improve functionality of optoelectronic devices. We theoretically study the modification of transport properties of bilayer graphene and bilayer heterostructures under a time-periodic external light field. The bulk electronic and transport properties are studied in a Landauer-type configuration by using the nonequilibrium Green's function formalism. To illustrate the behavior of the differential conductance of a bilayer contact under light illumination, we consider tight-binding models of bilayer graphene and graphene/hexagonal boron-nitride heterostructures. The non-adiabatic driving induces sidebands of the original band structure and opening of gaps in the quasienergy spectrum. In transport properties, the gap openings are manifested in a suppression of the differential conductance. In addition to suppression, an external light field induces an enhancement of the differential conductance if photoexcited electrons tunnel into or out of a Van~Hove singularity.
