有限长金属纳米碳管的量子尺寸效应

Quantum Size Effects in Finite-length Metallic Nanotubes

利用碳管的螺旋、旋转对称性 ,并沿螺旋方向附加一周期性边界条件 ,研究了有限长金属纳米碳管的量子化能级及电子波函数。发现 ,由于长度的限制导致一有限大小能隙的出现 ,能隙的大小随管的长度振荡并衰减。沿螺旋或管轴方向 ,费米面附近的波函数呈周期性振荡或常数形式 。

Quantized energy levels and electronic wave functions of finite-length metallic carbon nanotubes are studied by using the nanotube helical and rotational symmetries and a periodic boundary condition along the nanotube helical direction. Limiting the length of the nanotubes, a band-gap is open. Along both the helical and length direction, the wave functions near the Fermi level may periodically oscillate or keep constants, depending on the type of the nanotubes. The periods along the two directions may be different.