  Motivated by a recent optical-lattice experiment by Choi et al.[Science 352,
1547 (2016)], we discuss how domain-wall melting can be used to investigate
many-body localization. First, by considering noninteracting fermion models, we
demonstrate that experimentally accessible measures are sensitive to
localization and can thus be used to detect the delocalization-localization
transition, including divergences of characteristic length scales. Second,
using extensive time-dependent density matrix renormalization group
simulations, we study fermions with repulsive interactions on a chain and a
two-leg ladder. The extracted critical disorder strengths agree well with the
ones found in existing literature.
