Anomalous thermal transport in silicon-like nanowires with one-dimensional correlated disorder

Understanding how structural disorder affects phonon transport is critical for controlling thermal conduction in nanoscale materials. In this work, we investigate thermal transport in Si-like nanowires composed of layered atoms with one-dimensional correlated disorder. Using the nonequilibrium Green’s function method, we reveal that introducing correlation among atomic layers induces phonon Anderson localization at low-frequencies, leading to a nonmonotonic length dependence of thermal conductivity: it increases at short lengths but decreases beyond a critical size, in sharp contrast to the monotonic trend observed in random disorder. Despite having fewer mass interfaces, the correlated nanowires exhibit lower thermal conductivity than their random disorder counterparts when the nanowire length exceeds 70 nm. Frequency-resolved analysis shows that spatial correlation suppresses the transmission of low-frequency phonons and promotes their localization, while concurrently extending the localization length of mid- and high-frequency modes. This selective reshaping of phonon localization is responsible for the anomalous transport behavior. Our findings provide new insights into heat transport engineering via tailored disorder in low-dimensional materials.