Activation Energy of a Charged Soliton Pinned by Dopants in Polyacetylene
Activation Energy of a Charged Soliton Pinned by Dopants in Polyacetylene
复制标题
聚乙炔中掺杂剂钉扎的带电孤子的活化能
DOI：
10.1143/jpsj.64.2106
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发表时间：
1995
影响因子：
1.7
通讯作者：
Y. Ono
中科院分区：
文献类型：
--
作者：
M. Kuwabara;Y. Ono
数值研究了掺杂离子钉扎带电孤子的激活能随掺杂浓度的变化。为了研究这个问题，使用了SU-Schrieffer-Heeger的模型，修正后的模型考虑了由于掺杂引起的长程电势。即使在低浓度区，掺杂剂也可以形成规则的晶格。激活能由孤子被掺杂剂钉扎的状态和孤子位于相邻掺杂剂之间的中点的状态之间的能量差定义。结果表明，随着掺杂浓度的增加，激活能迅速减小。通过引入链内电子-电子相互作用的影响，还发现孤子宽度是决定激活能的重要因素之一。通过动力学模拟研究了带电孤子从掺杂剂中脱钉的阈值电场。不出所料，结果是……
The activation energy of a charged soliton pinned by a dopant ion is numerically studied as a function of the dopant concentration. To investigate this problem, use is made of Su-Schrieffer-Heeger's model modified to involve the long-range potential due to the dopants. The dopants are assumed to form a regular lattice even in the low concentration region. The activation energy is defined by the energy difference between a state where the soliton is pinned by a dopant and another state where the soliton locates at a mid point between neighboring dopants. It is shown that the activation energy decreases rapidly with increase of the dopant concentration. It is also found through introducing the effect of the intrachain electron-electron interactions that the soliton width is one of the essential factors in determining the activation energy. The threshold electric field for the depinning of the charged soliton from a dopant is also numerically investigated by dynamical simulations. As expected from the result...