Dy-V magnetic interaction and local structure bias on the complex spin and orbital ordering in Dy$_{1-x}$Tb$_{x}$VO$_3$ (x\,=\,0 and 0.2)

TL;DR

This study investigates how Dy-Tb magnetic interactions and local structural distortions influence the complex spin and orbital ordering in Dy$_{1-x}$Tb$_{x}$VO$_3$, revealing phase coexistence and field-dependent magnetic transitions.

Contribution

It provides new insights into the role of Dy-V magnetic coupling and local structure effects on spin and orbital phases in Dy-Tb vanadates.

Findings

Coexistence of G-OO/C-AF and C-OO/G-AF phases in Dy0.8Tb0.2VO3

Dy moment ordering induces phase transition at 12 K

Magnetic fields suppress Dy order and influence phase stability

Abstract

The spin and orbital ordering in Dy$_{1-x}$Tb$_{x}$VO$_3$ (x\,=\,0 and 0.2) was studied by measuring x-ray powder diffraction, magnetization, specific heat, and neutron single crystal diffraction. The results show that G-OO/C-AF and C-OO/G-AF phases coexist in Dy$_{0.8}$Tb$_{0.20}$VO$_3$ in the temperature range 2\,K$\sim$60\,K and the volume fraction of each phase is temperature and field dependent. The ordering of Dy moments at T*\,=\,12\,K induces a transition from G-OO/C-AF to a C-OO/G-AF phase. Magnetic fields suppress the long range order of Dy moments and thus the C-OO/G-AF phase below T*. The polarized moments induced at the Dy sublattice by external magnetic fields couple to the V 3d moments and this coupling favors the G-OO/C-AF state. Also discussed is the effect of the Dy-V magnetic interaction and local structure distortion on the spin and orbital ordering in Dy$_{1-x}$Tb$_{x}$VO$_3$.