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arXiv · 2005.10771

Tunnel Magnetoresistance in Self-Assemblies of Exchange Coupled Core/Shell Nanoparticles

Fernando Fabris·Enio Lima Jr.·Cynthia Quinteros·Lucas Nener·Mara Granada·Martín Sirena·Roberto D. Zysler·Horacio E. Troiani·Víctor Leborán·Francisco Rivadulla·Elin L. Winkler
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Abstract

We report the precise control of tunneling magnetoresistance (TMR) in devices of self-assembled core/shell Fe$_3$O$_4$/Co$_{1-x}$Zn$_x$Fe$_2$O$_4$ nanoparticles ($0\leq x\leq 1$). Adjusting the magnetic anisotropy through the content of Co$^{2+}$ in the shell, provides an accurate tool to control the switching field between the bistable states of the TMR. In this way, different combinations of soft/hard and hard/soft core/shell configurations can be envisaged for optimizing devices with the required magnetotransport response.

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Fernando Fabris, Enio Lima Jr., Cynthia Quinteros, Lucas Nener, Mara Granada, Martín Sirena, Roberto D. Zysler, Horacio E. Troiani, Víctor Leborán, Francisco Rivadulla, Elin L. Winkler. 2020-05-21. Tunnel Magnetoresistance in Self-Assemblies of Exchange Coupled Core/Shell Nanoparticles. https://doi.org/10.1103/physrevapplied.11.054089

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