μ⁺SR Study of K₂Cr₈O₁₆ Under Hydrostatic Pressure

Abstract

In this study, the magnetic ground state of the hollandite type material K 2 Cr 8 O 16 was tuned by externally applied pressure and investigated using µ + SR method in Zero-field (ZF) and weak-transverse field (wTF) configurations. As a result, the obtained magnetic transition temperature for the measured pressures differs notably from magnetization measurements. Moreover, both wTF and ZF data reveal a transition between two different magnetically ordered states at low temperatures for higher pressures. Further theoretical and experimental studies are currently being planned in order to elucidate the detailed nature of the magnetically ordered phase.

Magnetic phase diagram of K2Cr8O16 clarified by high-pressure muon spin spectroscopy

“…One of the hollandite materials that has attracted a lot of attention for both theoretical and experimental studies is K 2 Cr 8 O 16 13–26 . This compound has a tetragonal structure, space group I 4/ m 27 , and displays a rare mixed valence state, 2Cr 3+ + 6Cr 4+ .…”

Na-ion dynamics in the solid solution NaxCa1−xCr2O4 studied by muon spin rotation and neutron diffraction

“…There are very few realizations of this phenomenon in actual samples: beyond NaCr 2 O 4 , another material that exhibits the Cr 3+ /Cr 4+ mixed-valence state is K 2 Cr 8 O 18 . 20 This rare condition is responsible for the unconventional low temperature microscopic properties 21 that make NaCr 2 O 4 a fascinating study case also from a fundamental research perspective. 22 The compound crystallizes in the orthorhombic space group 62 ( Pnma ), in which Cr cations occupy two distinct crystallographic positions (labelled as Cr I and Cr II in Fig.…”