Spin-Orbit-Lattice Entangled State in A2⁢MgReO6 (A=Ca, Sr, Ba) Revealed by Resonant Inelastic X-Ray Scattering

The 5d1 ordered double perovskites present an exotic playground for studying novel multipolar physics due to large spin-orbit coupling. We present Re L3 edge resonant inelastic x-ray scattering (RIXS) results that reveal the presence of the dynamic Jahn-Teller effect in the A2MgReO6 (A ¼ Ca, Sr, Ba) family of 5d1 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 5d1 double perovskites.

https://opac.ll.chiba-u.jp/da/curator/900122586/

American Physical Society

Journal Article

Physical Review Letters

133

3

036501-1

036501-6

2024-07-19

https://doi.org/10.1103/PhysRevLett.133.036501

eng

publisher

(c)2024 American Physical Society