Sub-Terahertz Excitations in Manganites with Commensurate Charge Order
Sub-Terahertz Excitations in Manganites with Commensurate Charge Order
复制标题
具有相应电荷顺序的锰氧化物中的亚太赫兹激发
DOI：
10.1007/s10948-008-0366-4
复制
发表时间：
2009
影响因子：
1.8
通讯作者：
J. García
中科院分区：
文献类型：
--
作者：
A. Nucara;P. Maselli;P. Calvani;R. Sopracase;M. Ortolani;G. Gruener;M. Cestelli Guidi;U. Schade;J. García
在亚THz区首次观测到了具有公度电荷有序(CO)的La-Ca、Nd-Sr和Bi-Sr锰氧化物的光学电导。下面，观察到与边带相关的有序温度TCO清晰的峰。它们分别被分配给被钉扎的相位子，以及相位子和振幅的组合。在La_1−n/8Can/8MnO_3(n=5，6)中，可以确定电声子耦合、CO系统的有效质量及其对介电常数的贡献。它们的值支持用CDW方法描述La-Ca锰氧化物中的CO。在TCO>；500K和耦合较强的Bi0.5Sr0.5MnO_3中，只有组合带被清晰地探测到。
The optical conductivity of La–Ca, Nd–Sr, and Bi–Sr manganites with commensurate charge order (CO) has been first observed in the sub-THz region. Below, the ordering temperature TCO well-defined peaks are observed, associated with side bands. They are assigned to pinned phasons, and to combinations of phasons and amplitudons, respectively. In La1−n/8Can/8MnO3 with n=5, 6, one can thus determine the electron-phonon coupling, the effective mass of the CO system, and its contribution to the dielectric constant. Their values support a description of the CO in La–Ca manganites in terms of a CDW approach. In Bi0.5Sr0.5MnO3, where TCO> 500 K and the coupling is stronger, only the combination bands are clearly detected.