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arXiv · 1211.3808

Parallel-leaky capacitance equivalent circuit model for MgO magnetic tunnel junctions

Ajeesh M. Sahadevan·Kalon Gopinadhan·Charanjit S. Bhatia·Hyunsoo Yang
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Abstract

The capacitance of MgO based magnetic tunnel junctions (MTJs) has been observed to be magnetic field dependent. We propose an equivalent circuit for the MTJs with a parallel-leaky capacitance (Cl) across the series combination of geometric and interfacial capacitance. The analysis of junctions with different tunneling magnetoresistance values suggests higher Cl for low TMR junctions. Using Cole-Cole plots the capacitive nature of MTJs is manifested. Fitting with Maxwell-Wagner capacitance model validates the RC parallel network model for MTJs and the extracted field dependent parameters match with the experimental values.

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Ajeesh M. Sahadevan, Kalon Gopinadhan, Charanjit S. Bhatia, Hyunsoo Yang. 2012-11-16. Parallel-leaky capacitance equivalent circuit model for MgO magnetic tunnel junctions. https://doi.org/10.1063/1.4760279

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