The self-organized vacancy order in Pr${}_9$Ge${}_{16}$

Abstract

In this work, we report the discovery of a new crystal structure on the Ge-rich side of the Pr-Ge binary phase diagram. Using a high-temperature flux technique, we grew single crystals of $P{r}_{9}G{e}_{16}$, which adopt a previously unreported orthorhombic $Fdd$2 structure type featuring ordered Ge vacancies. We present the anisotropic magnetic properties and identify the crystallographic $b$ axis perpendicular to the crystal plane as the magnetic easy axis. Temperature-dependent resistivity measurements reveal metallic behavior with a distinct anomaly at $T_{\mathrm{C}}$ = 14.3 K. Hall resistivity data indicate that electron-like carriers dominate, with a carrier concentration on the order of $10^{27}{\mathrm{m}}^{-3}$. The magnetic order is readily suppressed by a magnetic field of approximately 0.4 T applied along the easy $b$ axis.

References in corpus (8)

• Mantid - Data Analysis and Visualization Package for Neutron Scattering and $\mu SR$ Experiments
• Use of frit-disc crucibles for routine and exploratory solution growth of single crystalline samples
• Magnetism and anomalous transport in the Weyl semimetal PrAlGe: Possible route to axial gauge fields
• Observation of Weyl fermions in a magnetic non-centrosymmetric crystal
• Single crystal investigation of proposed type-II Weyl semimetal CeAlGe
• Bulk single crystal growth of the theoretically predicted magnetic Weyl semimetals $R$AlGe ($R$ = Pr, Ce)
• Anisotropic Curie temperature materials
• Complex magnetic ordering in CeGe1.76 studied by neutron diffraction