Figure 3: Dispersion relations of the ion acoustic modes for warm dense aluminium with varying friction strength.
From: A strong diffusive ion mode in dense ionized matter predicted by Langevin dynamics
(a) Shows data from orbital-free density functional theory (OF-DFT) simulations, whereas (b) shows data from fully classical MD simulations. Both were run in the canonical ensemble at Te=Ti=3.5 eV and ρ=5.2 g cm−3, using a Langevin thermostat with different friction strengths, σ. The annotated numbers give the sound speeds of the ion acoustic waves in the system as obtained from the constant gradient at small wavenumbers, k.
