Thermal Rupture of Monatomic Metal Nanowires

Abstract

The present study deals with the problem of thermal stability and rupture of metal nanowires, considered here as a monatomic chain located on an atomically smooth crystalline substrate. Based on a recently developed Monte Carlo computational model, the simulation results reveal a scenario of nanowire breaking via formation of atomic vacancies. Depending on temperature, the fluctuations in the positions of the nanowire atoms generate wave-shaped nanowire configurations with specific active sites for breaking. This process is followed by formation of one-atom vacancies in the nanowire. Their overgrowth into vacancies of two, three and more atoms leads to permanent nanowire rupture and, hence, to loss of the nanowire electronic and other physical properties. The time evolution of the atomic-scale nanowire morphology and breaking mechanism are discussed in detail. The proposed model of nanowire rupture sheds light on the general problem of thermal stability of artificial atomic structures on crystal surfaces and their application to electronic and other devices with exotic physical features.