晶体学手性的控制和检测是一个重要而具有挑战性的科学问题。手征性具有从医学物理到宇宙学的广泛含义,包括磁性系统中的亲密但微妙的连接,例如Mn $_{1-x}$ Fe $_{x}$ Si。X射线衍射技术与共振或偏振变化的实验装置目前被用来表征晶格手性。我们使用理论计算证明了间接$K$边缘双磁振子共振非弹性X射线散射(RIXS)光谱作为一种可行的实验技术来区分晶体旋向性的可行性。我们应用自旋波理论,最近发现的$\sqrt {5}\times\sqrt {5}$空缺有序硫族化合物Rb $_{0.89}$ Fe $_{1.58}$ Se $_{2}$为现实的X射线实验设置参数(入射能量,偏振,和布拉格角)表明,计算RIXS光谱是敏感的基本手性(右或左)的晶格。引入了一个Flack参数的定义,它包含了左右手征晶格RIXS响应。结果表明,多带磁振子系统RbFeSe的RIXS响应来自带间和带内散射过程。这些RIXS峰的消失或存活对潜在的手性晶格取向敏感。这又允许识别两个手性晶格取向。
英文摘要:
The control and detection of crystallographic chirality is an important and challenging scientific problem. Chirality has wide ranging implications from medical physics to cosmology including an intimate but subtle connection in magnetic systems, for example Mn$_{1-x}$Fe$_{x}$Si. X-ray diffraction techniques with resonant or polarized variations of the experimental setup are currently utilized to characterize lattice chirality. We demonstrate using theoretical calculations the feasibility of indirect $K$ -edge bimagnon resonant inelastic X-ray scattering (RIXS) spectrum as a viable experimental technique to distinguish crystallographic handedness. We apply spin wave theory to the recently discovered $\sqrt {5}\times\sqrt {5}$ vacancy ordered chalcogenide Rb$_{0.89}$Fe$_{1.58}$Se$_{2}$ for realistic X-ray experimental set up parameters (incoming energy, polarization, and Bragg angle) to show that the computed RIXS spectrum is sensitive to the underlying handedness (right or left) of the lattice. A Flack parameter definition that incorporates the right- and left- chiral lattice RIXS response is introduced. It is shown that the RIXS response of the multiband magnon system RbFeSe arises both from inter- and intra- band scattering processes. The extinction or survival of these RIXS peaks are sensitive to the underlying chiral lattice orientation. This in turn allows for the identification of the two chiral lattice orientations.
Proposal for detecting spin-chirality terms in Mott insulators via resonant inelastic x-ray scattering
本文研究了共振非弹性X射线散射(RIXS)能否用于探测与自旋手征项S_i耦合的多体激发。(S_j x S_k)的近似解。我们发现,虽然自旋手征项一般不存在于通常的实验设置的RIXS,有实现这些条款的前景,如果人们认为,而不是散射附近的前边缘。然后,我们进行了详细的分析,正方形和戈薇晶格,三角形和蜂窝晶格的简要分析,其中我们表明,自旋手征性条款确实存在于所有上述晶格,但它们发生在我们的展开戈薇和蜂窝晶格的高阶。在U(1)Dirac自旋液体中出现的规范玻色子的背景下,还简要讨论了使用RIXS和拉曼光谱检测与自旋手征项耦合的激发的优点。
National Synchrotron Radiation Research Center(国家同步辐射研究中心);National Tsing Hua University(国立清华大学);Pohang University of Science and Technology(浦项工科大学);Rutgers University(罗格斯大学);Institute of Metal Physics(金属物理研究所);Ural Federal University(乌拉尔联邦大学);University of Tokyo(东京大学);National Yang Ming Chiao Tung University(国立阳明交通大学)
Circular Dichroism in Resonant Inelastic X-ray Scattering: Probing Altermagnetic Domains in MnTe
Waseda University(早稻田大学);Tohoku University(东北大学);Osaka Metropolitan University(大阪公立大学);Masaryk University(马萨里克大学);TU Wien(维也纳工业大学);Central European Institute of Technology, Masaryk University(马萨里克大学中欧技术研究所);Institute for Solid State Physics, TU Wien(维也纳工业大学固体物理研究所);Frontier Research Institute for Interdisciplinary Sciences, Tohoku University(东北大学跨学科科学前沿研究所);Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University(东北大学先进材料多学科研究所)
Probing Anomalous Inelastic Scattering in Spin-ice Ho$_2$Ti$_2$O$_7$ through Resonant Raman Spectroscopy
研究了(001)和(111)Ho $_2$ Ti $_2$ O $_7$单晶的室温非弹性散射特性。结构和组成分析以及吸收测量证实了所有样品的单晶相。利用六条不同的激光激发线,在非共振和两种不同的共振条件下对晶体进行了室温偏振拉曼光谱测量。对所有测量的光谱进行洛伦兹模型拟合分析,以确定共振和非共振条件下拉曼散射截面的差异。由于不同的极化配置和晶体学取向的拟合参数的变化,有助于确定它们的对称性,如果存在的话。为了定性地解释Ho $_2$ Ti $_2$ O $_7$中的反常散射结果,讨论了几种可能的散射途径
Parity Broken Chiral Spin Dynamics in Ba$_3$NbFe$_3$Si$_2$O$_{14}$
用非极化和极化非弹性中子散射研究了镧系镓酸盐Ba $_3$ NbFe $_3$ Si $_2$ O $_{14}$对映体纯晶体中手性螺旋调制120 $^{\circ}$磁序的自旋波激发.获得了手性基态的动力学指纹,通过(i)对结构手性负责的谱重不对称性和(ii)在整个能谱上观察到的自旋相关性的全手性来奇异化。自旋波元激发的内在手征性质的宏观时间反演对称性破缺的情况下示出。
Raman scattering study of anomalous charge-, spin-, and lattice-dynamics in the charge-ordered phase of ${\bf Bi}_{1-x}{\bf Ca}_x{\bf MnO}_3$ ($x>0.5$)
Paul Scherrer Institut(保罗谢勒研究所);Czech Technical University in Prague(布拉格捷克理工大学);ESRF - The European Synchrotron(欧洲同步辐射装置);National Cheng Kung University(国立成功大学)
Non-reciprocal circular dichroism of axial phonons coupled to ferro-rotational order
National Synchrotron Radiation Research Center(国家同步辐射研究中心);Department of Physics and Astronomy, The University of Tennessee(田纳西大学物理与天文系);Institute for Advanced Materials and Manufacturing, University of Tennessee(田纳西大学先进材料与制造研究所);Institute of Metal Physics(金属物理研究所);Department of Theoretical Physics and Applied Mathematics, Ural Federal University(乌拉尔联邦大学理论物理与应用数学系);Department of Physics and Materials Science, University of Luxembourg(卢森堡大学物理与材料科学系);Department of Physics, National Tsing Hua University(国立清华大学物理系)