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arXiv · 2005.08911

Remote Mesoscopic Signatures of Induced Magnetic Texture in Graphene

N. Arabchigavkani·R. Somphonsane·H. Ramamoorthy·G. He·J. Nathawat·S. Yin·B. Barut·K. He·M. D. Randle·R. Dixit·K. Sakanashi·N. Aoki·K. Zhang·L. Wang·W. -N. Mei·P. A. Dowben·J. Fransson·J. P. Bird
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Abstract

Mesoscopic conductance fluctuations are a ubiquitous signature of phase-coherent transport in small conductors, exhibiting universal character independent of system details. In this work, however, we demonstrate a pronounced breakdown of this universality, due to the interplay of local and remote phenomena in transport. Our experiments are performed in a graphene-based interaction-detection geometry, in which an artificial magnetic texture is induced in the graphene layer by covering a portion of it with a micromagnet. When probing conduction at some distance from this region, the strong influence of remote factors is manifested through the appearance of giant conductance fluctuations, with amplitude much larger than $e^2/h$. This violation of one of the fundamental tenets of mesoscopic physics dramatically demonstrates how local considerations can be overwhelmed by remote signatures in phase-coherent conductors

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N. Arabchigavkani, R. Somphonsane, H. Ramamoorthy, G. He, J. Nathawat, S. Yin, B. Barut, K. He, M. D. Randle, R. Dixit, K. Sakanashi, N. Aoki, K. Zhang, L. Wang, W. -N. Mei, P. A. Dowben, J. Fransson, J. P. Bird. 2020-05-18. Remote Mesoscopic Signatures of Induced Magnetic Texture in Graphene. https://doi.org/10.1103/physrevlett.126.086802

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