标题： V2O3反铁磁绝缘相中各向异性偶极矩的实验证据，来源于x射线共振布拉格衍射 显示英文标题

标题： Experimental evidence of anapolar moments in the antiferromagnetic insulating phase of V2O3 obtained from x-ray resonant Bragg diffraction

摘要： 我们研究了Mott-Hubbard绝缘体V$_2$O$_3$的反铁磁绝缘相，通过在钒K边缘的共振X射线布拉格衍射。结合从方位角扫描、线性入射偏振扫描以及将收集的数据拟合到已建立的化学I2/a和磁空间群导出的散射振幅中获得的信息，我们提供了各向异性偶极矩排列模式的证据（该排列模式源于宇称破坏与电磁场的耦合）。在空间群禁止的布拉格反射处收集的实验数据（方位角依赖性和偏振分析）在我们的模型中成功得到了解释，该模型基于钒的磁电多极矩。我们证明了所有类型的空间群禁止布拉格反射$(hkl)_m$中奇数$h$的共振X射线衍射强度是由E1-E2事件产生的。确定的张量参数为该材料的从头算计算提供了一个测试，这可以导致对V$_2$O$_3$物理性质更深入和更定量的理解。 显示英文摘要

摘要： We have investigated the antiferromagnetic insulating phase of the Mott-Hubbard insulator V$_2$O$_3$ by resonant x-ray Bragg diffraction at the vanadium K-edge. Combining the information obtained from azimuthal angle scans, linear incoming polarization scans and by fitting collected data to the scattering amplitude derived from the established chemical I2/a and magnetic space groups we provide evidence of the ordering motif of anapolar moments (which results from parity violation coupling to an electromagnetic field). Experimental data (azimuthal dependence and polarization analysis) collected at space-group forbidden Bragg reflections are successfully accounted within our model in terms of vanadium magnetoelectric multipoles. We demonstrate that resonant x-ray diffraction intensities in all space-group forbidden Bragg reflections of the kind $(hkl)_m$ with odd $h$ are produced by an E1-E2 event. The determined tensorial parameters offer a test for ab-initio calculations in this material, that can lead to a deeper and more quantitative understanding of the physical properties of V$_2$O$_3$.