Frontini Felix I, Johnstone Graham H J, Iwahara Naoya, Bhattacharyya Pritam, Bogdanov Nikolay A, Hozoi Liviu, Upton Mary H, Casa Diego M, Hirai Daigorou, Kim Young-June
Physics Department, <a href="https://ror.org/03dbr7087">University of Toronto</a>, 60 Saint George Street, Toronto, Ontario M5S 1A7, Canada.
Graduate School of Engineering, <a href="https://ror.org/01hjzeq58">Chiba University</a>, 1-33 Yayoi-cho, Inage-ku, Chiba-shi, Chiba 263-8522, Japan.
Phys Rev Lett. 2024 Jul 19;133(3):036501. doi: 10.1103/PhysRevLett.133.036501.
The 5d^{1} ordered double perovskites present an exotic playground for studying novel multipolar physics due to large spin-orbit coupling. We present Re L_{3} edge resonant inelastic x-ray scattering (RIXS) results that reveal the presence of the dynamic Jahn-Teller effect in the A_{2}MgReO_{6} (A=Ca, Sr, Ba) family of 5d^{1} double perovskites. The spin-orbit excitations in these materials show a strongly asymmetric line shape and exhibit substantial temperature dependence, indicating that they are dressed with lattice vibrations. Our experimental results are explained quantitatively through a RIXS calculation based on a spin-orbit-lattice entangled electronic ground state with the dynamic Jahn-Teller effect taken into consideration. We find that the spin-orbit-lattice entangled state is robust against magnetic and structural phase transitions as well as against significant static Jahn-Teller distortions. Our results illustrate the importance of including vibronic coupling for a complete description of the ground state physics of 5d^{1} double perovskites.
由于具有大的自旋轨道耦合，5d¹有序双钙钛矿为研究新型多极物理提供了一个奇特的平台。我们展示了Re L₃边共振非弹性X射线散射（RIXS）结果，这些结果揭示了在5d¹双钙钛矿的A₂MgReO₆（A = Ca、Sr、Ba）族中存在动态 Jahn-Teller 效应。这些材料中的自旋轨道激发显示出强烈不对称的线形，并且表现出显著的温度依赖性，表明它们与晶格振动相互作用。我们的实验结果通过基于考虑了动态 Jahn-Teller 效应的自旋轨道-晶格纠缠电子基态的RIXS计算进行了定量解释。我们发现自旋轨道-晶格纠缠态对磁相和结构相变以及显著的静态 Jahn-Teller 畸变具有鲁棒性。我们的结果说明了包括电子-振动耦合对于完整描述5d¹双钙钛矿基态物理的重要性。
