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arXiv · 1711.08204

Phase diagram for the Harper model of the honeycomb lattice

Geo Jose·Rajesh Malla·Varadharajan Srinivasan·Auditya Sharma·Suhas Gangadharaiah
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Abstract

The Harper equation arising out of a tight-binding model of electrons on a honeycomb lattice subject to a uniform magnetic field perpendicular to the plane is studied. Contrasting and complementary approaches involving von Neumann entropy, fidelity, fidelity susceptibility, multifractal analysis are employed to characterize the phase diagram. The phase diagram consists of three phases: two metallic phases and an insulating phase. A variant model where next nearest neighbor hopping is included, exhibits a mobility edge and does not allow for a simple single phase diagram characterizing all the eigenstates.

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Geo Jose, Rajesh Malla, Varadharajan Srinivasan, Auditya Sharma, Suhas Gangadharaiah. 2017-11-22. Phase diagram for the Harper model of the honeycomb lattice. https://doi.org/10.1088/1361-648x%2Faada3d

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