Width-induced metal-insulator transition in SrVO3 lateral nanowires spontaneously formed on the ultrathin film

Abstract

We investigated lateral nanowires at the topmost layer of SrVO3 (001) ultrathin films using in situ low-temperature scanning tunneling microscopy and spectroscopy. The nanowires were spontaneously formed in the topmost layer of SrVO3 with a (root 2x root 2)-R45 degrees reconstruction on the terrace of a (root 5x root 5)-R26.6 degrees reconstruction. The electronic states of nanowires were significantly influenced by the nanowire width. With reducing the nanowire width from 5.5nm to 1.7nm, the zero-bias conductance of nanowires steeply decreased toward zero, exhibiting a metal-insulator transition possibly driven by dimensional crossover, previously observed in thickness-reduced SrVO3 ultrathin films.