Persistent quantum vibronic dynamics in a $5d^1$ double perovskite oxide

Abstract

Quantum entanglement between the spin, orbital, and lattice degrees of freedom in condensed matter systems can emerge due to an interplay between spin-orbit and vibronic interactions. Heavy transition metal ions decorated on a face-centered cubic lattice, for example, in $5d^1$ double perovskites, are particularly suited to support these quantum entangled states, but direct evidence has not yet been presented. In this work, we report additional peaks in the low-energy spectra of a $5d^1$ double perovskite, Ba${}_2$CaReO${}_6$, which cannot be explained by adopting a purely classical description of lattice vibrations. Instead, our theoretical analysis demonstrates that these spectroscopic signatures are characteristic of orbital-lattice entangled states in Ba${}_2$CaReO${}_6$. Crucially, both theory and experiment demonstrate that these quantum-entangled states persist to low temperatures, despite the onset of multipolar order.

7 pages, 4 figures

References in corpus (14)

• Spin-orbit-entangled electronic phases in 4$d$ and 5$d$ transition-metal compounds
• Novel Magnetism and Local Symmetry Breaking in a Mott Insulator with Strong Spin Orbit Interactions
• Detection of multipolar orders in the spin-orbit-entangled 5d Mott insulator Ba2MgReO6
• The Jahn-Teller effect and spin--orbit coupling: friends or foes?
• Dynamic Jahn-Teller effect in the strong spin-orbit coupling regime
• Interplay between multipolar spin interactions, Jahn-Teller effect and electronic correlation in a $J_{eff}=\frac{3}{2}$ insulator
• The origin of magnetism in a supposedly nonmagnetic osmium oxide
• Phase Diagram of Ba${}_2$NaOsO${}_6$, a Mott insulator with strong spin orbit interactions
• Phase transition preceding magnetic long-range order in the double perovskite Ba2NaOsO6
• Spin-orbit-lattice entangled state in A${}_2$MgReO${}_6$ (A = Ca, Sr, Ba) revealed by resonant inelastic X-ray scattering
• Phase transition in the 5d1 double perovskite Ba2CaReO6 induced by high magnetic field
• Vibronic order and emergent magnetism in cubic $d^1$ double perovskites
• Interplay of superexchange and vibronic effects in the hidden order of Ba${}_2$MgReO${}_6$ from first principles
• Structure, heat capacity and Raman spectra of mm-sized Ba${}_2$MgWO${}_6$ single crystals synthesized by BaCl${}_2$-MgCl${}_2$ flux method

Cited by in corpus (2)

• Resonant inelastic X-ray scattering investigation of Hund's and spin-orbit coupling in $5d^2$ double perovskites
• Coupled-cluster approach to vibronic effects in resonant inelastic x-ray scattering of quantum materials: Application to a $5d^1$ rhenium oxide