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arXiv · 1403.4315

Spin Density Waves in the Hubbard model - A DMFT approach

Robert Peters·Norio Kawakami
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Abstract

We analyze spin density waves (SDWs) in the Hubbard model on a square lattice within the framework of inhomogeneous dynamical mean field theory (iDMFT). Doping the half-filled Hubbard model results in a change of the antiferromagnetic Néel state, which exists exactly at half filling, to a phase of incommensurate SDWs. Previous studies of this phase mainly rely on static mean field calculations. In this paper, we will use large-scale iDMFT calculations to study properties of SDWs in the Hubbard model. A great advantage of iDMFT over static mean field approaches is the inclusion of local screening effects and the easy access to dynamical correlation functions. Furthermore, this technique is not restricted to the Hubbard model, but can be easily used to study incommensurate phases in various strongly correlated materials.

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Robert Peters, Norio Kawakami. 2014-04-25. Spin Density Waves in the Hubbard model - A DMFT approach. https://doi.org/10.1103/physrevb.89.155134

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