Electrical noise inside the band gap of bilayer graphene

Aamir, Md Ali and Ghosh, Arindam (2019) Electrical noise inside the band gap of bilayer graphene. In: 2D MATERIALS, 6 (2).

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Abstract

Bilayer graphene (BLG), endowed with its electrostatically tunable band gap, plays a special role in next generation 2D materials based electronics. However, important aspects of its device characteristics are not fully understood, including in particular, the mechanism of electrical noise in its gapped state, which is essential to its operation. Here, we present the first systematic study of 1/f noise in conductance G in a dual-gated BLG as we tune the Fermi energy inside its large band gap. The normalized conductance noise <delta G(2)>/G(2) initially increases dramatically by over an order of magnitude, which our analysis indicates, as arising due to percolative charge transport. When the Fermi energy reaches the charge neutrality point, we observe a remarkably constant <delta G(2)> irrespective of the magnitude of band gap, even though G decreases exponentially with band gap. We discuss that this is likely to be consequence of fluctuations in activated charge carriers far from the Fermi energy, enabled by charge traps of the substrate. Our results provide a coherent description of low frequency electrical noise in gapped BLG, paving the way for its implementation in the next-generation devices as well as representing benchmark for other gapped 2D materials.

Item Type:	Journal Article
Publication:	2D MATERIALS
Publisher:	IOP PUBLISHING LTD
Additional Information:	Copyright for this article belongs to IOP Publishing.
Keywords:	bilayer graphene; 1/f noise; gapped 2D materials; device performance
Department/Centre:	Division of Interdisciplinary Sciences > Centre for Nano Science and Engineering Division of Physical & Mathematical Sciences > Physics
Date Deposited:	11 Mar 2019 10:09
Last Modified:	11 Mar 2019 10:09
URI:	http://eprints.iisc.ac.in/id/eprint/61918

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