Modulated magnetic structure in 57Fe doped orthorhombic YbMnO3: a M\"ossbauer study

TL;DR

This study uses 57Fe Mössbauer spectroscopy to reveal that the intermediate magnetic phase in 57Fe doped orthorhombic YbMnO3 is modulated and incommensurate, providing new insights into its magnetic structure.

Contribution

First Mössbauer study to characterize the incommensurate modulated magnetic structure in 57Fe doped o-YbMnO3.

Findings

The intermediate phase (38.0 K < T < 41.5 K) is modulated and incommensurate.

Mössbauer spectra shape analysis confirms the incommensurate magnetic structure.

The magnetic structure differs from the well-known low-temperature antiferromagnetic phase.

Abstract

In the orthorhombic manganites o-RMnO3, where R is a heavy rare earth (R = Gd-Yb), the Mn3+ sublattice is known to undergo two magnetic transitions. The low temperature phase has an antiferromagnetic structure (collinear or elliptical), which has been well characterized by neutron diffraction in most of these compounds. The intermediate phase, occurring in a narrow temperature range (a few K), is documented for R = Gd-Ho as a collinear modulated structure, incommensurate with the lattice spacings. We report here on a 57Fe M\"ossbauer study of 2% 57Fe doped o-YbMnO3, where the spin only Fe3+ ion plays the role of a magnetic probe. From the analysis of the shape of the magnetic hyperfine M\"ossbauer spectra, we show that the magnetic structure of the intermediate phase in o-YbMnO3 (38.0 K < T < 41.5 K) is also modulated and incommensurate.