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arXiv · 1410.3315

Effective Hamiltonian for electron waves in artificial graphene: A first principles derivation

Sylvain Lannebère·Mário G. Silveirinha
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Abstract

We propose a first principles effective medium formalism to study the propagation of electron waves in semiconductor heterostructures with a zero-band gap. Our theory confirms that near the K-point the dynamics of a two-dimensional electron gas modulated by an external electrostatic potential with honeycomb symmetry is described by the same pseudospinor formalism and Dirac massless equation as a graphene monolayer. Furthermore, we highlight that even though other superlattices based on semiconductors with a zincblende-type structure can have a zero band-gap and a linear energy-momentum dispersion, the corresponding effective medium Hamiltonian is rather different from that of graphene, and can be based on a single-component wavefunction.

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Sylvain Lannebère, Mário G. Silveirinha. 2014-10-13. Effective Hamiltonian for electron waves in artificial graphene: A first principles derivation. https://doi.org/10.1103/physrevb.91.045416

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