Coupled spin, charge and orbital dynamics of low-dimensional cuprates

共振非弹性x射线散射（RIXS）在过去两年中得到了巨大的发展，现在是过渡金属氧化物中自旋、电荷和轨道激发最强大的动量分辨探针。只有另一种实验方法可以提供这些材料中电子激发的色散，即电子能量损失光谱（EELS）。然而，虽然RIXS能够以出色的灵敏度探测磁和轨道激发，但EELS非常适合研究电荷转移激发和等离子体激元。这个项目的想法是将RIXS的新功能与EELS和理论结合起来，形成一种新的、全面的方法来研究相关电子材料。这种方法将应用于低维铜，它构成了具有重大科学意义的定义良好的模型系统。第一个目标是进一步建立方法论。这将为第二个目标铺平道路，即研究新的铜材料：一维量子自旋液体和新的多腿阶梯系统的候选材料。通过这种独特的方法组合，我们的目标是对铜酸盐的集体自旋、电荷和轨道动力学以及相应的基本激发之间的耦合获得新的关键见解。将使用两个世界领先的设备：PSI维利根的RIXS设备和IFW德累斯顿的传输EELS。PSI Villigen和IFW Dresden的密切合作将汇集两个研究所的专业知识，并将产生显著的协同效应。

Resonant inelastic x-ray scattering (RIXS) has been subject to tremendous developments in the last 2 years and is now a most powerful momentum resolved probe for spin, charge and orbital excitations in transition metal oxides. There is only one other experimental method that provides access to the dispersion of electronic excitations in these materials, namely electron-energy loss spectroscopy (EELS). However, while RIXS enables to probe magnetic and orbital excitations with outstanding sensitivity, EELS is ideally suited for studies of charge transfer excitations and plasmons. The idea of this project is to combine the new capabilities of RIXS with EELS and theory into a novel, comprehensive approach for the study of correlated electron materials. This approach will be applied to low-dimensional cuprates, which constitute well-defined model-systems of large scientific relevance. The first goal is to further establish the methodology. This will then pave the way to the second goal, which is the study of new cuprate materials: candidates for one-dimensional quantum spin-liquids and new multiple-leg ladder systems. With this unique combination of methods, we aim to gain new key insights into the collective spin, charge and orbital dynamics of cuprates and the coupling between the corresponding elementary excitations. Two worldwide leading facilities will be used: the RIXS facility of the PSI Villigen and the transmission EELS of the IFW Dresden. The close collaboration of PSI Villigen and IFW Dresden will bring together the expertise of both institutes and will create significant synergies.