Coherent phonon transport and Anderson localization in WS2/MoS2 superlattices
Publication in Communications Physics!
Understanding the interplay between coherent and incoherent phonon transport is essential for designing efficient nanoscale devices. Although many studies focus on three-dimensional materials, we still lack a systematic understanding of wave-based transport and localization effects in twodimensional systems. Here we show that perfectly periodic heterostructures made of alternating layers of tungsten disulfide and molybdenum disulfide exhibit a non-monotonic pattern in their thermal conductance profile, a direct signature of coherent transport. In contrast, introducing aperiodicity leads to the emergence of Anderson localization, visible as an exponential decay of phonon transmission with superlattice length. Using first-principles combined with atomistic Green-function calculations, we quantify how structural disorder suppresses in-plane thermal conductance through coherent localization rather than incoherent scattering. These findings clarify how distinct coherent transport regimes arise in ordered versus aperiodic two-dimensional superlattices, and establish principles for controlling heat flow through wave interference in layered materials. |
Fig. 1: Left: Computational model of the WS2/MoS2 superlattice. The central superlattice region (total length L = N x a, period D =M x a) is connected to semi-infinite WS2 leads. Mo (brown), W (grey), S (yellow).
Right: Ensemble-averaged transmission 〈T〉 as a function of device length L. The linear trend on the semi-log scale (red squares, right axis) confirms the exponential decay characteristic of Anderson localization.
Ref : A. Sebbar, S. Tyagi, N. Cavassilas, Y. Guo, Z. Zhang, S. Volz & M. Bescond "Coherent phonon transport and Anderson localization in WS2/MoS2 superlattices," Commun. Phys. 9, 298 (2026).
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