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arXiv · 2010.09192

Theory of the Strain Engineering of Graphene Nanoconstrictions

Masahiko Hayashi·Hideo Yoshioka·Hikari Tomori·Akinobu Kanda
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Abstract

Strain engineering is one of the key technologies for using graphene as an electronic device: the strain-induced pseudo-gauge field reflects Dirac electrons, thus opening the so-called conduction gap. Since strain accumulates in constrictions, graphene nanoconstrictions can be a good platform for this technology. On the other hand, in the graphene nanoconstrictions, Fabry-Perot type quantum interference dominates the electrical conduction at low bias voltages. We argue that these two effects have different strain dependence; the pseudo-gauge field contribution is symmetric with respect to positive (tensile) and negative (compressive) strain, whereas the quantum interference is antisymmetric. As a result, a peculiar strain dependence of the conductance appears even at room temperatures.

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Masahiko Hayashi, Hideo Yoshioka, Hikari Tomori, Akinobu Kanda. 2020-10-19. Theory of the Strain Engineering of Graphene Nanoconstrictions. https://doi.org/10.7566/jpsj.90.023701

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