Delerue C, Lannoo M, Allan G
Institut d'Electronique et de Microelectronique du Nord, Departement Institut Superieur d'Electronique du Nord, 41 boulevard Vauban 59046 Lille Cedex, France.
Phys Rev Lett. 2000 Mar 13;84(11):2457-60. doi: 10.1103/PhysRevLett.84.2457.
We present calculations of the one- and two-particle excitations in silicon nanocrystals. The one-particle properties are handled in the GW approximation, and the excitonic gap is obtained from the Bethe-Salpeter equation. We develop a tight binding version of these methods to treat clusters up to 275 atoms. The self-energy and Coulomb corrections almost exactly cancel each other for crystallites with radius larger than 0.6 nm. The result of this cancellation is that one-particle calculations give quite accurate values for the excitonic gap of crystallites in the most studied range of sizes.
我们展示了硅纳米晶体中单粒子和双粒子激发的计算结果。单粒子性质采用GW近似处理，激子能隙由贝里-萨尔皮特方程获得。我们开发了这些方法的紧束缚版本来处理多达275个原子的团簇。对于半径大于0.6 nm的微晶，自能和库仑修正几乎完全相互抵消。这种抵消的结果是，在最常研究的尺寸范围内，单粒子计算给出了微晶激子能隙的相当准确的值。
