A piezoelectric, strain-controlled antiferromagnetic memory insensitive to magnetic fields

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Antiferromagnetic (AFM) materials offer potential for fast and robust spintronic devices.
• Controlling magnetism with electric fields in piezoelectric materials can reduce energy consumption.
• Existing AFM memory often requires thermal heating or magnetic fields for writing information.

Purpose of the Study:

• To explore the use of piezoelectric strain to control the resistance states of antiferromagnetic materials.
• To develop a novel strain-controlled antiferromagnetic memory device.
• To investigate the performance of such devices under various magnetic field conditions.

Main Methods:

• Investigated resistance changes in high-Néel-temperature antiferromagnet MnPt induced by piezoelectric strain.
• Fabricated and tested tunnel junctions integrating MnPt for enhanced electroresistance.
• Evaluated device stability and performance in magnetic fields up to 60 T.

Main Results:

• Discovered two non-volatile resistance states in MnPt at room temperature and zero electric field.
• Demonstrated that the strain-induced resistance switching is insensitive to magnetic fields.
• Achieved a tunnelling anisotropic magnetoresistance of ~11.2% at room temperature in integrated tunnel junctions.

Conclusions:

• A piezoelectric, strain-controlled antiferromagnetic memory device has been successfully demonstrated.
• The device is fully operational in strong magnetic fields and shows potential for low-energy, high-density memory applications.
• This approach offers a promising alternative to conventional magnetic field or current-driven switching methods.