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Zero magnetization in a disordered (La(1-x/2)Bi(x/2))(Fe(0.5)Cr(0.5))O(3) uncompensated weak ferromagnet
K Vijayanandhini1, Ch Simon, V Pralong
1CRISMAT, UMR 6508, CNRS-ENSICAEN, Université de Caen, 14050 Caen, France.
Summary
This study investigates bismuth-lanthanum iron-chromium oxide perovskites, revealing an uncompensated weak ferromagnet with unusual zero magnetization behavior above 450 K. The findings contrast with previous suggestions of spin glass properties.
Area of Science:
- Materials Science
- Solid State Physics
- Magnetism
Background:
- Orthorhombic perovskites with the Pnma space group are known for potential magnetic properties.
- Previous studies suggested spin glass behavior in similar compounds.
Purpose of the Study:
- To investigate the magnetic properties of (La(1-x/2)Bi(x/2))(Fe(0.5)Cr(0.5))O(3) perovskites for 0≤x≤1.
- To understand the origin of the peculiar zero magnetization behavior.
Main Methods:
- X-ray diffraction to confirm crystal structure.
- AC magnetic susceptibility measurements to analyze magnetic behavior.
- Temperature-dependent magnetization studies.
Main Results:
- The compound exhibits an orthorhombic perovskite structure (Pnma), consistent with disordered iron and chromium at B sites.
- An uncompensated weak ferromagnetism was observed with a magnetic transition above 450 K.
- A peculiar zero magnetization phenomenon occurred between 100 and 160 K, varying with composition.
- AC susceptibility ruled out spin glass or cluster glass behavior.
Conclusions:
- The investigated perovskite is an uncompensated weak ferromagnet, not a spin glass.
- The zero magnetization phenomenon is attributed to canted ferromagnetic domains and antiferromagnetically coupled chromium-iron clusters.
- This behavior is linked to Cr-O-Fe interactions within the perovskite structure.
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