Spin-flip processes of polarons by magnetic impurities in conjugated polymers.
Spin-flip processes of polarons by magnetic impurities in conjugated polymers.
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DOI：
10.1063/1.3247189
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发表时间：
2009-10
期刊：
影响因子：
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通讯作者：
H Zhao;Yuguang Chen;Yao Yao-Yao;Chang-qin Wu;Xu-Ming Zhang;Z. An
中科院分区：
文献类型：
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作者：
H Zhao;Yuguang Chen;Yao Yao-Yao;Chang-qin Wu;Xu-Ming Zhang;Z. An
采用自适应含时密度矩阵重整化群方法，研究了含有磁性杂质的高分子链中极化子的自旋翻转过程。在外加电场的驱动下，同时携带1/2自旋和电荷+/-e的极化子在聚合物链中以恒定的速度移动。当极化子通过一个特定的位置，通过自旋交换作用与磁性杂质耦合时，如果它的自旋与杂质自旋反平行，就会观察到一个自旋翻转过程。我们的结果表明，自旋翻转几率随自旋交换积分的增大而增大，并随自旋交换积分的增大而增大。此外，还讨论了极化子与杂质之间自旋态交换的一些可能的应用。
By employing an adaptive time-dependent density-matrix-renormalization-group method, the spin-flip process of polarons is investigated in a polymer chain with magnetic impurities. Being driven by an external electric field, a polaron carrying both spin 1/2 and charge +/-e moves at a constant speed in the polymer chain. When the polaron passes through a specific site, which couples to a magnetic impurity via spin-exchange interaction, a spin-flip process is observed if its spin is antiparallel to the impurity spin. Our results show that the spin-flip probability is enhanced by the on-site Coulomb interaction and increases with increase in the spin-exchange integral. Additionally, some possible applications of the spin-state swap between the polaron and the impurity are discussed.