方钴矿Ce1-xGdxFe4P12（x = 0.001）单晶中Gd3 + ESR精细结构的热激活交换窄化
Thermally activated exchange narrowing of the Gd3+ ESR fine structure in a single crystal of Ce1-xGdxFe4P12 (x = 0.001) skutterudite
摘要：
本文报道了Gd ~（3+）掺杂的半导体填充方钴矿化合物Ce_（1-x）Gd_xFe_（4-p）_（12）（x = 0.001）的电子自旋共振（ESR）测量结果。当温度T从T = 150 K变化到T = 165 K时，Gd ~（3+）的ESR精细结构和超精细结构合并成一个宽的非均匀单共振.在T = 200 K时，谱线变窄，随着T的进一步增加，共振变得均匀，热展宽为1.1（2）Oe/K。这些结果表明，这些特征的起源可能与热激活机制的微妙的相互依赖性有关，这些机制结合了：i）跨T依赖的半导体赝能隙的激活导电载流子的密度随T增加; ii）由于交换相互作用引起的Gd 3 + Korringa弛豫过程，J_{fd} S.s，Gd 3+局域磁矩和热激活传导载流子之间的关系; iii）在过大的（Fe 2 P3）4笼内的稀土离子的相对弱的限制电势，这使得稀土元素在T = 148 K以上成为更响的爱因斯坦振荡器。我们认为Gd 3+离子的晃动，通过运动窄化机制，也有助于ESR精细和超精细结构的合并。
英文摘要：
We report electron spin resonance (ESR) measurements in the Gd3+ doped semiconducting filled skutterudite compound Ce1-xGdxFe4P12 (x = 0.001). As the temperature T varies from T = 150 K to T = 165 K, the Gd3+ ESR fine and hyperfine structures coalesce into a broad inhomogeneous single resonance. At T = 200 K the line narrows and as T increases further, the resonance becomes homogeneous with a thermal broadening of 1.1(2) Oe/K. These results suggest that the origin of these features may be associated to a subtle interdependence of thermally activated mechanisms that combine: i) an increase with T of the density of activated conduction-carriers across the T-dependent semiconducting pseudogap; ii) the Gd3+ Korringa relaxation process due to an exchange interaction, J_{fd}S.s, between the Gd3+ localized magnetic moments and the thermally activated conduction-carriers and; iii) a relatively weak confining potential of the rare-earth ions inside the oversized (Fe2P3)4 cage, which allows the rare-earths to become rattler Einstein oscillators above T = 148 K. We argue that the rattling of the Gd3+ ions, via a motional narrowing mechanism, also contributes to the coalescence of the ESR fine and hyperfine structure.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
