Tuning the orbital-lattice fluctuations in the mixed spin-dimer system Ba$_{3-x}$Sr$_{x}$Cr$_{2}$O$_{8}$
Autor: | Gazizulina, Alsu, Quintero-Castro, Diana Lucia, Wulferding, Dirk, Teyssier, Jeremie, Prokes, Karel, Yokaichiya, Fabiano, Schilling, Andreas |
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Rok vydání: | 2018 |
Předmět: | |
Zdroj: | Phys. Rev. B 98, 144115 (2018) |
Druh dokumentu: | Working Paper |
DOI: | 10.1103/PhysRevB.98.144115 |
Popis: | In $A_{3}$Cr$_{2}$O$_{8}$, where $A$ = Sr or Ba, the Cr$^{5+}$ ions surrounded by oxygen ions in a tetrahedral coordination are Jahn-Teller active. The Jahn-Teller distortion leads to a structural transition and a related emergence of three twinned monoclinic domains below the structural phase transition. This transition is highly dynamic over an extended temperature range for $A$ = Sr. We have investigated mixed compounds Ba$_{3-x}$Sr$_{x}$Cr$_{2}$O$_{8}$ with $x=2.9$ and $x=2.8$ by means of X-ray and neutron diffraction, Raman scattering and calorimetry. Based on the obtained evolution of the phonon frequencies, we find a distinct suppression of the orbital-lattice fluctuation regime with increasing Ba content. This stands in contrast to the linear behaviour exhibited by unit cell volumes, atomic positions and intradimer spin-spin exchange interactions. Comment: 6 pages, 5 figures |
Databáze: | arXiv |
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