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 (√2 × √2)-R45° reconstruction on the terrace of a (√5 × √5)-R26.6° reconstruction. The electronic states of nanowires were significantly influenced by the nanowire width. With reducing the nanowire width from 5.5 nm to 1.7 nm, 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.