  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 N\'{e}el 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.

Quantum Gases;Computational Physics