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arXiv · 0906.1564

Tight-binding modeling and low-energy behavior of the semi-Dirac point

S. Banerjee·R. R. P. Singh·V. Pardo·W. E. Pickett
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Abstract

We develop a tight-binding model description of semi-Dirac electronic spectra, with highly anisotropic dispersion around point Fermi surfaces, recently discovered in electronic structure calculations of VO$_2$/TiO$_2$ nano-heterostructures. We contrast their spectral properties with the well known Dirac points on the honeycomb lattice relevant to graphene layers and the spectra of bands touching each other in zero-gap semiconductors. We also consider the lowest order dispersion around one of the semi-Dirac points and calculate the resulting electronic energy levels in an external magnetic field. We find that these systems support apparently similar electronic structures but diverse low-energy physics.

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S. Banerjee, R. R. P. Singh, V. Pardo, W. E. Pickett. 2009-06-08. Tight-binding modeling and low-energy behavior of the semi-Dirac point. https://doi.org/10.1103/physrevlett.103.016402

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