Quantum Monte Carlo simulations of antiferromagnetism in ultracold fermions on optical lattices within real-space dynamical mean-field theory

N. Blümer; E. V. Gorelik

doi:10.1016/j.cpc.2010.07.011

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arXiv · 1006.2716

Quantum Monte Carlo simulations of antiferromagnetism in ultracold fermions on optical lattices within real-space dynamical mean-field theory

N. Blümer·E. V. Gorelik

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Abstract

We present a massively parallel quantum Monte Carlo based implementation of real-space dynamical mean-field theory for general inhomogeneous correlated fermionic lattice systems. As a first application, we study magnetic order in a binary mixture of repulsively interacting fermionic atoms harmonically trapped in an optical lattice. We explore temperature effects and establish signatures of the Néel transition in observables directly accessible in cold-atom experiments; entropy estimates are also provided. We demonstrate that the local density approximation (LDA) fails for ordered phases. In contrast, a "slab" approximation allows us to reach experimental system sizes with O(10^5) atoms without significant loss of accuracy.

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N. Blümer, E. V. Gorelik. 2010-06-14. Quantum Monte Carlo simulations of antiferromagnetism in ultracold fermions on optical lattices within real-space dynamical mean-field theory. https://doi.org/10.1016/j.cpc.2010.07.011

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