Bound state energy of a Coulomb impurity in gapped bilayer graphene
Bound state energy of a Coulomb impurity in gapped bilayer graphene
复制标题
带隙双层石墨烯中库仑杂质的束缚态能
DOI：
10.1103/physrevb.89.041405
复制
发表时间：
2013
影响因子：
3.7
通讯作者：
M. Voloshin
中科院分区：
文献类型：
--
作者：
B. Skinner;B. Shklovskii;M. Voloshin
垂直电场的应用在双层石墨烯中诱导了带隙，并且在色散关系中也产生了“墨西哥帽”结构。这种结构对于电子与库仑杂质的类氢束缚态具有不同寻常的意义。我们计算了这种类氢状态的基态能量作为所施加的层间电压和有效精细结构常数的函数。与传统的氢原子不同，即使在基态，所产生的波函数也有许多节点。此外，电子态在小电压和大电压下都经历了“原子跃迁”进入狄拉克连续谱。
Application of a perpendicular electric field induces a band gap in bilayer graphene, and it also creates a ``Mexican hat'' structure in the dispersion relation. This structure has unusual implications for the hydrogen-like bound state of an electron to a Coulomb impurity. We calculate the ground state energy of this hydrogen-like state as a function of the applied interlayer voltage and the effective fine structure constant. Unlike in the conventional hydrogen atom, the resulting wave function has many nodes even in the ground state. Further, the electron state undergoes ``atomic collapse'' into the Dirac continuum both at small and large voltage.