强磁场下铱基烧绿石结构A2Ir2O7中的自旋轨道耦合、几何阻挫及其相互作用研究

在铱基化合物中，普遍存在较强的自旋轨道耦合效应。由于自旋轨道耦合能、电子-电子作用关联能、晶场劈裂能相当，产生了复杂的竞争和平衡，导致了复杂的基态。而在铱基烧绿石结构A2Ir2O7中，除了上述几种能量的竞争，还存在A位的几何阻挫效应。我们知道，强磁场手段可以对其中的阻挫效应、自旋有序、自旋轨道耦合进行有效的调制。因此，本项目拟用强磁场手段，对铱基烧绿石结构A2Ir2O7中的自旋轨道耦合、几何阻挫、自旋有序结构等进行深入研究，揭示强磁场对几何阻挫和自旋轨道耦合的影响，进而对自旋轨道耦合、几何阻挫、自旋相互作用等之间的竞争和合作机制进行探索，并对自旋有序、金属-绝缘转变等物理现象进行研究。

In Iridium compounds, there widely exists strong spin-orbital coupling. The approximation between energies of spin-orbital coupling, electron-electron interaction, and crystal field, results into complex competition and balance, which generates a variety of ground states. In the pyrochlore structural A2Ir2O7, there exists geometry frustration on the A-sites in addition to the above interactions. As we know, the high magnetic field can effectively modify the frustration, spin ordering, and spin-orbital coupling. Therefore, this program is designed to study the spin-orbital coupling, the geometry frustration, the spin ordering, as well as the interplay between them by the high magnetic field. The aim of this program is to investigate the effect of the high magnetic field on the geometry frustration and spin-orbital coupling, which will discover the interplay between the spin-orbital coupling, geometry frustration, and spin interaction. Furthermore, the mechanisms of spin ordering and metal-insulator phase transition in this system will be clarified.