Development of probing orbital symmetry related to the formation of Fermi surfaces by polarization-dependent hard x-ray photoemission

我们开发了一种极化依赖的硬x射线光发射系统，通过该系统可以实验地探测固体中导电电子的轨道特征以及它们的能量和动量。在x射线偏振开关中，采用双片单晶金刚石作为移相器。此外，还引入了硬x射线聚焦技术（低至25微米）来提高吞吐量，其强度比以前的条件强6倍。通过使用该系统，我们成功地揭示了电子之间的库仑排斥不可忽略的强相关材料的电子结构。

We have developed the polarization-dependent hard x-ray photoemission system, by which the orbital character of conduction electrons in solids in addition to their energies and momenta can experimentally been probed. For the x-ray polarization switching, two-plate single-crystalline diamonds have been employed as a phase shifter. Furthermore, hard x-ray focusing technique (down to 25 micrometer) has also been introduced to improve the throughput, by which the intensity has become six times stronger than the previous condition. By using this system we have succeeded in revealing the electronic structure of strongly correlated materials where the Coulomb repulsion between the electrons is not negligible.