Magnetostriction-polarization coupling in multiferroic Mn₂MnWO₆.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Solid State Chemistry

Background:

• Double corundum-related polar magnets are key for multiferroic and magnetoelectric applications in spintronics.
• Magnetoelectric coupling is challenging to achieve and has only been observed in Ni3TeO6 among known double corundum compounds.

Purpose of the Study:

• To synthesize a new polar and antiferromagnetic corundum derivative, Mn2MnWO6, under high pressure.
• To investigate the magnetoelectric properties and potential applications of this new material.

Main Methods:

• High-pressure synthesis.
• Magnetic measurements including field-induced metamagnetic phase transitions.
• Second harmonic generation effect measurements.
• Pyroresponse and dielectric measurements.
• Piezoresponse force microscopy (PFM) imaging and spectroscopy.

Main Results:

• Successfully synthesized Mn2MnWO6 with the Ni3TeO6-type structure.
• Observed first-order field-induced metamagnetic phase transitions at 58 K.
• Demonstrated high spontaneous polarization (~63.3 μC·cm⁻²).
• Provided evidence for magnetostriction-polarization coupling and qualitative indication of magnetoelectric coupling.
• Showed switchable polarization using PFM.

Conclusions:

• Mn2MnWO6 is a new polar magnet with significant spontaneous polarization and indications of magnetoelectric coupling.
• The material exhibits field-induced metamagnetic transitions and magnetostriction-polarization coupling.
• Further research on single crystal/thin film specimens is warranted to fully explore the magnetoelectric effect.