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arXiv · 1811.10269

Unconventional charge and spin dependent transport properties of a graphene nanoribbon with line-disorder

Sudin Ganguly·Saurabh Basu·Santanu K. Maiti
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Abstract

Electronic transport with a line (or a few lines) of Anderson type disorder in a zigzag graphene nanoribbon is investigated in presence of Rashba spin-orbit interaction. Such line disorders give rise to peculiar behavior in both charge as well as spin-polarized transmission in the following sense. In the weak disorder regime, the charge transport data show Anderson localization up to a certain disorder strength, beyond which the extended states emerge and start dominating over the localized states. These results are the hallmark signature of a selectively disordered (as opposed to bulk disorder) graphene nanoribbon. However, the spin-polarized transport shows a completely contradicting behavior. Further, the structural symmetries are shown to have an important role in the spintronic properties of the nanoribbons. Moreover, the edge-disorder scenario (disorder selectively placed at the edges) seems to hold promise for the spin-filter and switching device applications.

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Sudin Ganguly, Saurabh Basu, Santanu K. Maiti. 2018-11-26. Unconventional charge and spin dependent transport properties of a graphene nanoribbon with line-disorder. https://doi.org/10.1209/0295-5075%2F124%2F57003

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