Huang S W, Liu Y T, Lee J M, Chen J M, Lee J F, Schoenlein R W, Chuang Y-D, Lin J-Y
MAX IV Laboratory, Lund University, PO Box 118, 221 00 Lund, Sweden. Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States of America. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States of America.
J Phys Condens Matter. 2019 May 15;31(19):195601. doi: 10.1088/1361-648X/ab05a2. Epub 2019 Mar 8.
X-ray absorption spectroscopy (XAS) is performed to study changes in the electronic structures of colossal magnetoresistance (CMR) and charged ordered (CO) La Ca MnO manganites with respect to temperature. The pre-edge features in O and Mn K-edge XAS spectra, which are highly sensitive to the local distortion of MnO octahedral, exhibit contrasting temperature dependence between CMR and CO samples. The seemingly counter-intuitive XAS temperature dependence can be reconciled in the context of polarons. These results help identify the most relevant orbital states associated with polarons and highlight the crucial role played by polarons in understanding the electronic structures of manganites.
进行X射线吸收光谱（XAS）分析，以研究巨磁电阻（CMR）和电荷有序（CO）的LaCaMnO锰氧化物的电子结构随温度的变化。O和Mn K边XAS光谱中的预边缘特征对MnO八面体的局部畸变高度敏感，在CMR和CO样品之间表现出相反的温度依赖性。在极化子的背景下，可以解释看似违反直觉的XAS温度依赖性。这些结果有助于确定与极化子相关的最相关轨道状态，并突出极化子在理解锰氧化物电子结构中所起的关键作用。
