Anomalous resistance change in nanocrystalline metallic systems

Abstract

Metallic chains of silver and copper particles respectively with diameters ~4-5 nm have been grown within an ion exchanged glass ceramic. The samples exhibit anomalous resistance change as the temperature is lowered from 300 to 80 K. Initially they show a metal-like behaviour with a rather unusually large variation of resistance as a function of temperature. As the temperature is raised again a semiconductor-like resistance change is observed. This is believed to arise due to a large thermally induced tensile stress causing a rupture of the metal particles. The resulting particles with smaller dimensions show quantum size effect resulting in the semiconductor-like behaviour. The resistance changes exhibit an hysteresis.