Angle resolved photoelectron spectroscopy study of hidden order and magnetic states in uranium compounds

铀基化合物中的磁性等有序态一直是凝聚态物理学的核心问题之一。特别是在Uru_2Si_2中观测到的隐序态已经引起了人们超过25年的关注。在本研究中，我们使用了角度分辨光电子能谱，这是了解材料电子结构、了解有序态起源的有力工具。我们发现负责这些有序态的u5f电子具有流动特性。这是理解有序态的重要基础。

The ordered states such as magnetism in uranium based compounds have been one of the central issues in condensed matter physics. Especially, the hidden order state observed in Uru_2Si_2 has been attracting much attention for more than 25 years. In the present study, we have performed angle-resolved photoelectron spectroscopy, which is a powerful tool to understand electronic structure of materials, to understand the origin of those ordered states. We have found that U 5f electrons, which are responsible for those ordered states, have an itinerant character. This is very important basis for the understanding of these ordered states.