Theory of giant magnetoresistance at misfit interfaces

Daichi Asahi; Naoto Nagaosa

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arXiv · 1302.7108

Theory of giant magnetoresistance at misfit interfaces

Daichi Asahi·Naoto Nagaosa

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Abstract

We study theoretically the resistance at the interface between the two planar systems with different lattice constants a and b. The resistance and the effect of the magnetic field depends sensitively on the ratio a/b. The size of the enlarged unit cell $\lambda = n_Aa = n_Bb$ ($n_A$, $n_B$: integers) is the crucial quantity, and the magnetic flux penetrating this enlarged unit cell determines the oscillation of the resistance. Therefore, the magnetoresistance is very much enhanced at (nearly) incommensurate relation between a and b.

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Daichi Asahi, Naoto Nagaosa. 2013-02-28. Theory of giant magnetoresistance at misfit interfaces. https://arxiv.org/abs/1302.7108

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