Glasslike ordering and spatial inhomogeneity of magnetic structure in Ba3FeRu2O9: Role of Fe/Ru site disorder

Middey, Srimanta and Ray, Sugata and Mukherjee, K and Paulose, PL and Sampathkumaran, EV and Meneghini, C and Kaushik, SD and Siruguri, V and Kovnir, Kirill and Sarma, DD (2011) Glasslike ordering and spatial inhomogeneity of magnetic structure in Ba3FeRu2O9: Role of Fe/Ru site disorder. In: Physical Review B: Condensed Matter and Materials Physics, 83 (14).

PDF Glasslike.pdf - Published Version Restricted to Registered users only Download (887kB) | Request a copy

Abstract

Several doped 6H hexagonal ruthenates, having the general formula Ba3MRu2O9, have been studied over a significant period of time to understand the unusual magnetism of ruthenium metal. However, among them, the M = Fe compound appears different since it is observed that unlike others, the 3d Fe ions and 4d Ru ions can easily exchange their crystallographic positions, and as a result many possible magnetic interactions become realizable. The present study involving several experimental methods on this compound establishes that the magnetic structure of Ba3FeRu2O9 is indeed very different from all other 6H ruthenates. Local structural study reveals that the possible Fe/Ru site disorder further extends to create local chemical inhomogeneity, affecting the high-temperature magnetism of this material. There is a gradual decrease of Fe-57 Mossbauer spectral intensity with decreasing temperature (below 100 K), which reveals that there is a large spread in the magnetic ordering temperatures, corresponding to many spatially inhomogeneous regions. However, finally at about 25 K, the whole compound is found to take up a global glasslike magnetic ordering.

Item Type:	Journal Article
Publication:	Physical Review B: Condensed Matter and Materials Physics
Publisher:	The American Physical Society
Additional Information:	Copyright of this article belongs to The American Physical Society.
Department/Centre:	Division of Chemical Sciences > Solid State & Structural Chemistry Unit
Date Deposited:	18 Jul 2011 08:27
Last Modified:	18 Jul 2011 08:27
URI:	http://eprints.iisc.ac.in/id/eprint/39084

Actions (login required)

View Item