Superparamagnetism in MgO-based magnetic tunnel junctions with a thin pinned ferromagnetic electrode

Superparamagnetism in MgO-based magnetic tunnel junctions with a thin pinned ferromagnetic electrode

MgO-based magnetic tunnel junctions have been fabricated with a thin Co40Fe40B20 CoFeB layer in the pinned synthetic antiferromagnetic CoFe/Ru/CoFeB stack. An inverted tunneling magnetoresistance is observed due to the unbalanced synthetic antiferromagnet. Superparamagnetic nanoparticles form when the CoFeB layer is thinner than 1.5 nm, and an abnormal temperature dependence of the junction res...

Ferromagnetic resonance and damping properties of CoFeB thin films as free layers in MgO-based magnetic tunnel junctions

Magnetic tunnel junctions with MgO-EuO composite tunnel barriers

Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. The chalcogenide compound EuO is best known as a highly efficient spin-filter tunnel barrier material. Using the mo...

MgO-based double barrier magnetic tunnel junctions with thin free layers

The free layer thickness tfree in double barrier magnetic tunnel junctions DMTJs based on crystalline MgO barriers and CoFeB ferromagnetic layers has been varied from 0.5 to 3.0 nm in order to investigate its effect on the magnetic and electrical properties. One obvious feature of DMTJs with tfree 1 nm is the absence of sharp free layer switching in the TMR curves, which can be explained by the...

Memristive switching of MgO based magnetic tunnel junctions

The search for nonvolatile memory concepts has a massive impact on the development of nanoscopic systems with adjustable electrical properties. Capacitor-like structures composed of insulating materials sandwiched between metallic electrodes are envisioned to overcome the limitations associated with conventional charge storage devices and may open the road to neuromorphic computing. Together wi...