Metamagnetic Behavior in a Quadruple Perovskite Oxide.

Area of Science:

• Materials Science
• Solid-State Physics
• Magnetism

Background:

• Complex oxides with multiple magnetic ions are crucial for advanced electronic applications.
• Understanding the interplay between different electron systems (e.g., 3d and 4f) is key to designing novel magnetic materials.
• Cerium (Ce)-based oxides are of particular interest due to the unique properties of Ce ions.

Purpose of the Study:

• To synthesize and characterize a novel cubic quadruple perovskite oxide, CeMn3Cr4O12.
• To investigate the magnetic properties and transitions within this complex oxide.
• To explore the influence of 3d-electron magnetic sublattices on 4f-electron magnetic moments.

Main Methods:

• High-pressure and high-temperature synthesis (8 GPa, 1273 K).
• X-ray absorption spectroscopy (XAS) for elemental state determination.
• Magnetic susceptibility measurements to identify magnetic transitions and phenomena.

Main Results:

• Successful synthesis of cubic quadruple perovskite oxide CeMn3Cr4O12.
• XAS confirmed Ce ions are in the trivalent state (Ce3+).
• Observed three independent antiferromagnetic transitions at ~10 K (Ce), 46 K (Mn), and 133 K (Cr).
• Discovered a magnetic field-induced antiferromagnetic-to-ferromagnetic (metamagnetic) transition in Ce3+ 4f moments below 20 K.
• Demonstrated the role of 3d-electron magnetic sublattices in the metamagnetism of 4f-electron moments.

Conclusions:

• CeMn3Cr4O12 is a rare example of metamagnetism in Ce3+-oxides.
• The study highlights a new aspect of 3d-4f complex electron systems.
• This work provides insights into the design of advanced magnetic materials with tunable properties.