Abstract
The interplay of charge, spin, and lattice degrees of freedom in matter leads to various forms of ordered states through phase transitions. An important subclass of these phenomena of complex materials is charge ordering (CO), mainly driven by mixed-valence states. We discovered by combining the results of electrical resistivity (), specific heat, susceptibility (), and single crystal x-ray diffraction (SC-XRD) that with the monoclinic tunnel type lattice (space group ) exhibits an unconventional CO at room temperature while retaining metallicity. The temperature-dependent SC-XRD results show successive phase transitions with superlattice reflections at and below (365 K) and only at between and (630 K). We interpreted these as evidence for the formation of an unconventional CO. It reveals a strong first-order phase transition in the electrical resistivity at (cooling) = 345 K and (heating) = 365 K. We argue that the origin of the phase transition is due to the localized Ru electrons. The results of our finding reveal an unique example of mixed valance heavy ions.
3 More- Received 30 March 2018
DOI:https://doi.org/10.1103/PhysRevB.98.085113
©2018 American Physical Society
Physics Subject Headings (PhySH)
Synopsis
Unusual Properties of a Ruthenium-Based Crystal
Published 7 August 2018
Experiments on a ruthenium-based material uncover an electron-ordering pattern that leads to surprising macroscopic behavior.
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