Quantum Transport Properties Of Graphene/h-BN Heterostructure Controlled By Electronic Field

In recent years,van der Waals heterostructures which are the stacking of twodimensional crystals have attracted considerable interests.Utilizing the characteristics of two-dimensional crystals layered structure,we can select two-dimensional crystals with different physical properties and stack them together in a specific way to purposely obtain various structures we want.Among these,the graphene/h-BN van der Waals heterostructure is one of the most typical representative.Study continues about the graphene/h-BN heterostructure,but so far,there has been little discussion about electronic structure of graphene/h-BN heterostructure nanoribbon(GBNNR).we thus think that it is important to study the electron structure and transport properties of GBNNR.Based on tight-binding model and Green’s function method,we systematically study the electronic structure and transport properties of GBNNR under the boundary potential,interlayer potential and vertical magnetic field,and got some meaningful conclusions.Firstly,we study the electronic structure and transport properties of graphene/h-BN controlled by boundary potential and magnetic field.The band structure of zigzag-edged graphene/h-BN heterostructure nanoribbon(ZGBNNR)shows a small gap and four edge bands.An effective way to individually manipulate the edge state by the boundary potentials is proposed.It is shown that the boundary potential can not only shift and deform the edge bands,but also modify the energy gap.The boundary potential can change the distribution of the edge states,resulting in an interesting evolution of the quantized conductance.Secondly,we study the electronic structure and transport properties of the graphene/h-BN controlled by interlayer potential and magnetic field.We show that an electric field applied in the direction perpendicular to the layers significantly modifies the electronic structure of the whole system,including shifts and other deformations of energy bands,which can allow to control the value of the energy gap.We show the band structure with a perpendicular magnetic field.We find that the boundary bands connecting the intermediate flat band are bent and deformed,increasing the boundary conduction channel of the system.Changes in the band structure result in an interesting evolution of the quantized conductance.In summary,we have studied the electronic band structure of the ZGBNNR by a tight-binding model.These results provide a simple and effective way to manipulate the electronic structure and transport property in graphene/h-BN heterostructure.Various modified bilayer systems could play a crucial role in the future nanoelectronics and we hope that our result will be helpful to the application of electronic equipment in the future.