@article{ISI:000332179900021,
 abstract = {We present a nonequilibrium strong-coupling approach to inhomogeneous
systems of ultracold atoms in optical lattices. We demonstrate its
application to the Mott-insulating phase of a two-dimensional
Fermi-Hubbard model in the presence of a trap potential. Since the
theory is formulated self-consistently, the numerical implementation
relies on a massively parallel evaluation of the self-energy and the
Green's function at each lattice site, employing thousands of CPUs.
While the computation of the self-energy is straightforward to
parallelize, the evaluation of the Green's function requires the
inversion of a large sparse 10(d) x 10(d) matrix, with d > 6. As a
crucial ingredient, our solution heavily relies on the smallness of the
hopping as compared to the interaction strength and yields a widely
scalable realization of a rapidly converging iterative algorithm which
evaluates all elements of the Green's function. Results are validated by
comparing with the homogeneous case via the local-density approximation.
These calculations also show that the local-density approximation is
valid in nonequilibrium setups without mass transport.},
 article-number = {023306},
 author = {Dirks, Andreas and Mikelsons, Karlis and Krishnamurthy, H. R. and
Freericks, James K.},
 doi = {10.1103/PhysRevE.89.023306},
 eissn = {1550-2376},
 issn = {1539-3755},
 journal = {PHYSICAL REVIEW E},
 month = {FEB 21},
 number = {2},
 orcid-numbers = {Mikelsons, Karlis/0000-0003-2540-0687
Freericks, James K/0000-0002-6232-9165},
 researcherid-numbers = {Mikelsons, Karlis/C-9147-2015
Freericks, James K/D-7502-2011},
 times-cited = {4},
 title = {Simulation of inhomogeneous distributions of ultracold atoms in an
optical lattice via a massively parallel implementation of
nonequilibrium strong-coupling perturbation theory},
 unique-id = {ISI:000332179900021},
 volume = {89},
 year = {2014}
}