Perpendicular Manganite Magnetic Tunnel Junctions Induced by Interfacial Coupling.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Spintronics

Background:

• Half-metallic La_2/3Sr_1/3MnO₃ (LSMO) offers high spin polarization ideal for magnetic tunnel junctions (MTJs).
• In-plane magnetic anisotropy of LSMO limits memory density, necessitating perpendicular tunneling for future applications.

Purpose of the Study:

• To design and fabricate manganite-based MTJs exhibiting perpendicular magnetic anisotropy (PMA).
• To investigate spin-dependent tunneling behaviors in these perpendicular MTJs.

Main Methods:

• Fabrication of MTJs using alternately stacked cobaltite and manganite layers.
• Characterization of interfacial coupling to induce PMA.
• Measurement of spin-dependent tunneling with out-of-plane magnetic fields.

Main Results:

• Demonstrated strong PMA in the fabricated manganite-based MTJs.
• Observed spin-dependent tunneling behaviors under an out-of-plane magnetic field.
• Identified direct tunneling as dominant at low bias and thermionic emission/oxygen vacancies at high bias.

Conclusions:

• Successfully realized perpendicular tunneling in manganite-based MTJs.
• PMA induced by interfacial coupling is crucial for device performance.
• Opens new avenues for designing all-oxide spintronic devices.