Magnetic phase transitions in Ta/CoFeB/MgO multilayers

Abstract

We study thin films and magnetic tunnel junction nanopillars based on Ta/Co${}_{20}$Fe${}_{60}$B${}_{20}$/MgO multilayers by electrical transport and magnetometry measurements. These measurements suggest that an ultrathin magnetic oxide layer forms at the Co${}_{20}$Fe${}_{60}$B${}_{20}$/MgO interface. At approximately 160 K, the oxide undergoes a phase transition from an insulating antiferromagnet at low temperatures to a conductive weak ferromagnet at high temperatures. This interfacial magnetic oxide is expected to have significant impact on the magnetic properties of CoFeB-based multilayers used in spin torque memories.

References in corpus (7)

• Towards ferroelectrically-controlled magnetism: Magnetoelectric effect in Fe/BaTiO3 multilayers
• Bias-driven large power microwave emission from MgO-based tunnel magnetoresistance devices
• Voltage-Induced Ferromagnetic Resonance in Magnetic Tunnel Junctions
• Ultralow-current-density and bias-field-free spin-transfer nano-oscillator
• Precise determination of the spectroscopic g-factor using broadband ferromagnetic resonance spectroscopy
• Single-shot time-domain studies of spin-torque-driven switching in magnetic tunnel junctions
• Time Domain Mapping of Spin Torque Oscillator Effective Energy

Cited by in corpus (5)

• Theory of inertial spin dynamics in anisotropic ferromagnets
• Interface moment dynamics and its contribution to spin-transfer torque switching process in magnetic tunnel junctions
• Terahertz cavity magnon polaritons
• Self-stabilizing exchange-mediated spin transport
• Controlling selection rules for magnon scattering in nanomagnets by spatial symmetry breaking