The interplay between the non-Hermiticity and dimensionality gives rise to
exotic characteristics in higher dimensions, with one representative phenomenon
known as the geometry-dependent skin effect (GDSE), which refers to that the
localization of extensive eigenstates depends on the system's geometry under
open boundary conditions. In this paper, we demonstrate the emergence of GDSE
in a two-dimensional sp optical ladder lattice with on-site atom loss, which
can be manifested by anisotropic dynamics of Bloch oscillations in the bulk of
the system. By applying a static force in different directions, the wave-packet
dynamics retrieve the complex energy spectra with either nonzero or zero
spectral winding number, indicating the presence or absence of skin
accumulation in the corresponding directions, respectively. Our results reveal
that the GDSE has an intrinsic anisotropic bulk dynamics independent of
boundary conditions, and offer its realization and detection in quantum
systems.Comment: 16 pages, 13 figure