1. Persistent quantum vibronic dynamics in a $5d^1$ double perovskite oxide
- Author
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Iwahara, Naoya, Soh, Jian-Rui, Hirai, Daigorou, Živković, Ivica, Wei, Yuan, Zhang, Wenliang, Galdino, Carlos, Yu, Tianlun, Ishii, Kenji, Pisani, Federico, Malanyuk, Oleg, Schmitt, Thorsten, and Rønnow, Henrik M
- Subjects
Condensed Matter - Strongly Correlated Electrons - 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., Comment: 7 pages, 4 figures
- Published
- 2024