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arXiv · 1012.5950

Spectral properties of the three-dimensional Hubbard model

Abstract

We present momentum resolved single-particle spectra for the three-dimensional Hubbard model for the paramagnetic and antiferromagnetically ordered phase obtained within the dynamical cluster approximation. The effective cluster problem is solved by continuous-time Quantum Monte Carlo simulations. The absence of a time discretization error and the ability to perform Monte Carlo measurements directly in Matsubara frequencies enable us to analytically continue the self-energies by maximum entropy, which is essential to obtain momentum resolved spectral functions for the N'eel state. We investigate the dependence on temperature and interaction strength and the effect of magnetic frustration introduced by a next-nearest neighbor hopping. One particular question we address here is the influence of the frustrating interaction on the metal insulator transition of the three-dimensional Hubbard model.

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Sebastian Fuchs, Emanuel Gull, Matthias Troyer, Mark Jarrell, Thomas Pruschke. 2011-06-09. Spectral properties of the three-dimensional Hubbard model. https://doi.org/10.1103/physrevb.83.235113

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