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arXiv · 1710.10260

Exceptional Lattice Green's Functions

Samuel Savitz·Marcus Bintz
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Abstract

The three exceptional lattices, $E_6$, $E_7$, and $E_8$, have attracted much attention due to their anomalously dense and symmetric structures which are of critical importance in modern theoretical physics. Here, we study the electronic band structure of a single spinless quantum particle hopping between their nearest-neighbor lattice points in the tight-binding limit. Using Markov chain Monte Carlo methods, we numerically sample their lattice Green's functions, densities of states, and random walk return probabilities. We find and tabulate a plethora of Van Hove singularities in the densities of states, including degenerate ones in $E_6$ and $E_7$. Finally, we use brute force enumeration to count the number of distinct closed walks of length up to eight, which gives the first eight moments of the densities of states.

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Samuel Savitz, Marcus Bintz. 2017-10-25. Exceptional Lattice Green's Functions. https://arxiv.org/abs/1710.10260

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