Structure, Stability, and Quantum Conductivity of Small Diameter Silicon Nanowires

Structures and energetics of various types of silicon nanowires have been investigated using both quantum and classical molecular dynamics simulations to determine the most stable forms. The tetrahedral type nanowires have been found to be the most stable and, surprisingly, the polycrystalline forms of nanowires, while having the smallest surface to bulk ratio, are found to be the least stable. We also show that the cagelike nanowires have greater thermal stability than the tetrahedral nanowires. Furthermore, their electrical conducting properties are found to be better than those of tetrahedral nanowires, suggesting useful molecular electronic applications.