  In this work, we investigate numerically the transport properties of a 2D
complex plasma crystal using diffusion of coplanar dust lattice waves. In the
limit where the Hamiltonian interactions can be decoupled from the
non-Hamiltonian effects, we identify two distinct types of wave transport:
Anderson-type delocalization and long-distance excitation. We use a
recently-developed spectral approach to evaluate the contribution of the
Anderson problem and compare it to the results of the simulation. The benefit
of our approach to transport problems is twofold. First, we employ a highly
tunable macroscopic hexagonal crystal, which exhibits many-body interactions
and allows for the investigation of transport properties at the kinetic level.
Second, the analysis of the transport problem in 2D is provided using an
innovative spectral approach, which avoids the use of scaling and boundary
conditions. Thus, the combination of theoretical calculation with simulation
results allows for the study of important characteristics of this open system.
The major deviation between the predicted and observed wave dynamics is a
long-distance lattice excitation, which occurs even when the initial
perturbation does not spread from the center to the exterior of the crystal. In
the decoupled Hamiltonian regime, this effect can be contributed to the dust
lattice interaction with the plasma environment.
