Determining the nature of the high energy quasi-circular dynamic correlations in cuprates with polarimetric RIXS

Dynamic fluctuations from periodic charge order correlations pervade the phase diagram of cuprate superconductors, perhaps more so than superconductivity. Recent advances in the energy resolution of resonant inelastic x-ray scattering (RIXS) instruments operating in soft x-ray regime enabled the detection of these fluctuations over energy and momentum. We recently performed two Cu-L3 RIXS studies on Bi2Sr2CaCu2O8+x (Bi2212) [2-3] and discovered dynamic fluctuations peaking at |q|=qCO along ALL in-plane directions in double layer Bi2212 – a ring-like pattern with finite energy-loss and radius equal to charge order wave vector magnitude. These correlations connect to the static charge order in the cuprates given the |q|=qCO relation. However, the charge-like nature of these dynamic correlations has not yet been experimentally determined. We propose using polarimetric RIXS to identify whether the high-energy quasi-circular dynamic correlations in Bi2212 are charge or spin in nature.

周期性电荷序关联产生的动态涨落遍布铜氧化物超导体的相图，其普遍性或许超过超导性本身。近年来，工作于软X射线波段的共振非弹性X射线散射（RIXS）仪器在能量分辨率上取得的进展，使得探测这些涨落在能量和动量空间的分布成为可能。我们近期对Bi2Sr2CaCu2O8+x（Bi2212）开展了两项铜L3边RIXS研究[2-3]，发现在双层Bi2212中，动态涨落在所有面内方向上均在|q|=qCO处出现峰值——呈现为一种具有有限能量损失、半径等于电荷序波矢大小的环状图案。鉴于|q|=qCO的关系，这些关联与铜氧化物中的静态电荷序存在联系。然而，这些动态关联的类电荷本质尚未通过实验确定。我们提议利用偏振RIXS技术，来鉴别Bi2212中高能准环状动态关联的本质究竟是电荷型还是自旋型。