Spin disorder in a stacking polytype of a layered magnet

TL;DR

This study introduces a new layered magnetic material, 3R-Na2MnTeO6, with a stacking polytype structure exhibiting low-dimensional magnetism, spin disorder, and complex magnetic correlations without long-range order.

Contribution

The paper reports the synthesis and characterization of a novel stacking polytype of Na2MnTeO6 with unique structural and magnetic properties not previously documented.

Findings

Identified a new stacking polytype with ABC-type stacking and R-3 symmetry.

Observed dominant antiferromagnetic interactions without long-range order down to 0.5 K.

Detected a structural transition at ~23 K potentially linked to Na displacements.

Abstract

Strongly correlated ground states and exotic quasiparticle excitations in low-dimensional systems are central research topics in the solid state research community. The present work develops a new layered material and explores the physical properties. Single crystals of 3R-Na2MnTeO6 were synthesized via a flux method. Single crystal x-ray diffraction and transmission electron microscopy reveal a crystal structure with ABC-type stacking and an R-3 space group, which establishes this material as a stacking polytype to previously reported 2H-Na2MnTeO6. Magnetic and heat capacity measurements demonstrate dominant antiferromagnetic interactions, the absence of long-range magnetic order down to 0.5 K, and field-dependent short range magnetic correlations. A structural transition at ~ 23 K observed in dielectric measurements may be related to displacements of the Na positions. Our results demonstrate that 3R-Na2MnTeO6 displays low-dimensional magnetism, disordered structure and spins, and the system displays a rich structure variety.