Polarons in organic ferromagnets
Polarons in organic ferromagnets
复制标题
有机铁磁体中的极化子
DOI：
10.1016/j.orgel.2018.01.020
复制
发表时间：
2018
影响因子：
3.2
通讯作者：
G. C. Hu
中科院分区：
文献类型：
--
作者：
Y. Y. Miao;S. Qiu;G. P. Zhang;J. F. Ren;C. K. Wang;G. C. Hu
采用考虑电子-晶格相互作用的类Anderson-like模型，对含自旋自由基的准一维有机铁磁体中极化子的形成进行了理论研究。在额外的电子的存在下，观察到的自旋和电荷密度的扭曲在主链和自由基。在主链中可以形成受分数电荷和自旋限制的类似极化子的晶格畸变，其中振幅通过主链和自由基之间的电子跳跃以及电子-电子相互作用来调谐。由于极化子晶格畸变导致低能电子对自旋和电荷的非对称修正，导致自旋和电荷的位置不一致。给出了不同电子跳跃和电子-电子强度下极化子形成的相图。的情况下，一个非零的现场之间的自由基和主链的能量差进行了讨论。由于主链与自旋自由基之间的电荷转移，在主链中发现了背景电荷密度波，阻碍了极化子的形成。
With an Anderson-like model including the electron-lattice interaction, the polaron formation in quasi-one-dimensional organic ferromagnets with spin radicals is investigated theoretically. In the presence of an additional electron, distortions of spin and charge densities are observed both in the main chain and radicals. A polaron-like lattice distortion confined with fractional charges and spins may be formed in the main chain, where the amplitude is tuned by the electron hopping between the main chain and radicals and the electron-electron interaction. The confined spins and charges are inconsistent in position, which is caused by the asymmetric modification of charges and spins from the low-energy electrons triggered by the polaron lattice distortion. A phase diagram of the polaron formation is given with different electron hopping and electron-electron strengths. The case of a nonzero on-site energy difference between the radicals and the main chain is also discussed. A background charge density wave is found in the main chain due to the charge transfer between the main chain and spin radicals, which hampers the formation of the polaron.