有机共轭聚合物材料中的齐纳隧穿

Zener Tunneling in Conjugated Polymers

基于扩展的SSH模型,采用非绝热动力学方法,研究高电场下一维有机共轭聚合物的电性质。发现在足够高的电场下,价带中的电子可以穿过带隙进入导带,即有机聚合物中的齐纳隧穿现象。伴随电子的带间隧穿,带隙消失,发生从绝缘体(半导体)到金属的相变(I-M相变),晶格结构同时发生重大变化。

Tunneling effect in one-dimensional conjugated polymers in the presence of an external electric field is studied within the framework of the tight-binding model and the nonadiabatic dynamical method. It is found that in a high electric field electrons can transit from the valence band to the conduction band, which is demonstrated to be Zener tunneling in organic semiconductors. The results also indicate a field-induced insulator-metal transition accompanied by the vanishing of the energy gap.