Ultra-low thermal conductivity of laterally arranged nanowire arrays through constriction engineering

Abstract

Nanostructured semiconductor materials exhibit remarkable thermal insulating properties compared to their bulk counterparts, making them highly promising for Thermo-Electric (TE) applications. This study employs computational tools to investigate the superior thermal insulating properties of Nanowire Chain (NWC) structures achieved through constriction engineering of laterally aligned nanowire arrays. Various surface and constriction modifications of NWCs are investigated to understand their impact on the thermal conductivity. The results demonstrate that the NWC structure achieves a substantial oneorder reduction in thermal conductivity compared to nanowires and nanosheets of similar dimensions. Moreover, this study evaluates the effectiveness of commonly used phonon suppression techniques, such as superlattice structures, shell alloying, and surface atom removal, in NWC configurations. The comprehensive analysis provides valuable insights into the phonon transport characteristics within different classes of NWCs, shedding light on their potential for diverse applications in the field of TE materials and thermal insulators.