【摘要】 基于第一性原理计算,以强极性极化材料作为衬底,提出一种打开双层石墨烯能隙的有效方法.应用表面功能化的氮化硼极性材料为衬底,使以AA和转角形式堆垛的双层石墨烯,其能隙打开到0.033 9 e V和0.032 5 eV.当以AB方式堆垛双层石墨烯时,在该衬底下其能隙可达到0.430 eV左右;且此能隙随衬底与双层石墨烯之间的堆垛方式的不同而发生微小变化.这表明该方法一方面能够通过改变双层石墨烯自身的堆垛方式来有效的改变其能隙大小;另一方面在AB堆垛情况下通过调整衬底与相邻石墨烯的堆垛方式可以对其能隙在0.430 eV附近进行微调.该方法在完美的保持双层石墨烯结构完整性的前提下,能够获得适用于光电子器件的能隙.相较于其他方法,该方法更加切实可行,能够促进石墨烯在半导体器件中的应用以及石墨烯技术的发展.更多还原

【Abstract】 Based on the first-principles calculations, An effective method was designed and put forward to opening the energy gap of the bilayer graphene by using strong polar materials as substrates. Taking surface-functionalized boron–nitrides as substrates, the energy gap of stacking order of AA and twisted bilayer graphene can be opened, which is 0.033 9 eV and 0.032 5 eV, respectively. Using the same method, the energy gap of stacking order of AB is also open and becomes larger, which is about 0.430 e V.And its gap can be slightly affected by the stacking orders of substrates with bilayer graphene. All of the results manifest that this method can tune the energy gap by changing the stacking orders of bilayer graphene. On the other hand, this method can also slightly tune the energy gap by changing the stacking orders between bilayer graphene(the AB stacking order) and substrates. The structural integrity of bilayer graphene is well-preserved, and the predicted energy gap is suitable for photo-electronic devices. Compared to other methods, the proposed method is more practical, accelerating the application of graphene in semiconductor devices and promoting the development of graphene technology.更多还原