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Nanoscale Tantalum layer impacting magnetic properties of tunnel junction-based molecular devices

Published online by Cambridge University Press:  23 July 2018

Pawan Tyagi*
Affiliation:
Mechanical Engineering, University of the District of Columbia, Washington DC-20008, USA Chemical and Materials Engineering, University of Kentucky, Lexington, KY-40566, USA
Tobias Goulet
Affiliation:
Mechanical Engineering, University of the District of Columbia, Washington DC-20008, USA
*
Address all correspondence to Pawan Tyagi at ptyagi@udc.edu
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Abstract

Magnetic tunnel junction can produce highly configurable molecular spintronics devices. This paper highlights a rather subtle attribute of magnetic tunnel junction fabrication that can lead to the very pronounced impact on magnetic properties of molecular spintronics device. We conducted magnetic studies to observe the effect of depositing ~5 nm Tantalum (Ta) on the top of a magnetic tunnel junction. We investigated the effect of Ta by using characterization techniques like ferromagnetic resonance, magnetometry, and polarized neutron reflectometry. Bridging paramagnetic molecules between the two ferromagnetic electrodes of magnetic tunnel junctions with and without Ta top layer produced the very different magnetic response.

Type
Research Letters
Copyright
Copyright © Materials Research Society 2018 

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