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arXiv · 0901.0840

Weak Localization and Transport Gap in Graphene Antidot Lattices

J. Eroms·D. Weiss
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Abstract

We fabricated and measured antidot lattices in single layer graphene with lattice periods down to 90 nm. In large-period lattices, a well-defined quantum Hall effect is observed. Going to smaller antidot spacings the quantum Hall effect gradually disappears, following a geometric size effect. Lattices with narrow constrictions between the antidots behave as networks of nanoribbons, showing a high-resistance state and a transport gap of a few mV around the Dirac point. We observe pronounced weak localization in the magnetoresistance, indicating strong intervalley scattering at the antidot edges. The area of phase-coherent paths is bounded by the unit cell size at low temperatures, so each unit cell of the lattice acts as a ballistic cavity.

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J. Eroms, D. Weiss. 2009-09-16. Weak Localization and Transport Gap in Graphene Antidot Lattices. https://doi.org/10.1088/1367-2630%2F11%2F9%2F095021

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