Recent Raman experiments on the Kitaev material $α$-RuCl$_3$ have reported a finite Raman circular dichroism (RCD), revealing chiral phonon behaviour not expected from lattice symmetry alone. To explain this observation, we develop a diagrammatic framework for the spin-phonon coupled Kitaev model. We demonstrate that bare phonons contribute no RCD, but coupling to the chiral spin excitation continuum under an applied magnetic field renormalizes the phonon propagator, mixing real polarization eigenvectors into complex superpositions with finite angular momentum. This interaction-induced modification generates a nonzero RCD accompanied by characteristic Fano line shapes in the Raman response, reflecting interference between discrete phonons and the continuum. The resulting signal grows with magnetic field strength, consistent with experiment, and directly tracks the field-induced chirality of the spin sector. More broadly, our results establish RCD as a powerful probe of interaction-induced chiral phonons in correlated quantum materials.
Raman Circular Dichroism and spinon Quantum Geometry of Chiral Quantum Spin Liquids
Technical University of Munich（慕尼黑工业大学）；Munich Center for Quantum Science and Technology (MCQST)（慕尼黑量子科学与技术中心）；Institute for Advanced Study, Technical University of Munich（慕尼黑工业大学高等研究院）；University of Zürich（苏黎世大学）；School of Physics and Astronomy, University of Minnesota（明尼苏达大学物理与天文学学院）；University of Minnesota（明尼苏达大学）；Imperial College London（伦敦帝国理工学院）
Observation of a warped helical spin-texture in Bi$_2$Se$_3$ from circular dichroism angle-resolved photoemission spectroscopy
拓扑表面态与左旋和右旋圆偏振光的微分耦合是拓扑绝缘体的许多光自旋电子学应用的基础。在这里，我们报告的圆二色性的直接证据，从表面状态的Bi $_2$ Se $_3$使用基于激光的飞行时间角分辨光电子能谱。通过采用一种新的样品旋转分析，我们解决了不寻常的调制的圆二色性光电发射图案作为能量和动量的函数，这完美地模仿了预测，但迄今未观察到的三维扭曲的自旋纹理的表面状态。通过发展拓扑表面态光电子发射的微观理论，我们表明，这种相关性是自旋轨道耦合的自然结果。这些结果表明，我们的技术可能是一个强大的探针的自旋-轨道耦合材料的自旋织构一般。
Magnetic circular dichroism of THz modes and selection rules of Raman-active optical phonons in the polar altermagnet candidate \ce{Mn2Mo3O8}
University of Augsburg（奥格斯堡大学）；Kazan (Volga region) Federal University（喀山（伏尔加沿岸）联邦大学）；Max Planck Institute for Solid State Research（马克斯·普朗克固体研究所）；Budapest University of Technology and Economics（布达佩斯技术与经济大学）；HUN-REN Wigner Research Centre for Physics（匈牙利研究与教育网络维格纳物理研究中心）
Circular dichroism and bilayer splitting in the normal state of underdoped (Pb,Bi)$_2$Sr$_2$(Ca$_x$Y$_{1-x}$)Cu$_2$O$_{8+δ}$ and overdoped (Pb,Bi)$_2$Sr$_2$CaCu$_2$O$_{8+δ}$
