Metal-insulator transition in V 2 O 3 thin film caused by tip-induced strain

Natalia Alyabyeva (1) , Joe Sakai (1) , M. Bavencoffe (1) , J. Wolfman (1) , P. Limelette (1) , H. Funakubo (2) , A. Ruyter (1)

1 GREMAN - UMR 7347 - GREMAN (matériaux, microélectronique, acoustique et nanotechnologies)
2 TITECH - Tokyo Institute of Technology [Tokyo]

We have demonstrated pressure-induced transition in a c-axis oriented V2O3 thin film from strongly correlated metal to Mott insulator in a submicrometric region by inducing a local stress using contact atomic force microscopy. To have an access to a pressure range of sub-gigapascal, a tip with a large radius of 335 nm was prepared by chemical vapour deposition of platinum onto a commercial tip with a focused ion beam (FIB). The FIB-modified tip gives a good electrical contact at low working pressures (0.25-0.4 GPa) allowing unambiguously to evidence reversible metalinsulator transition in a pulsed laser-deposited V2O3 thin film by means of local investigations of current-voltage characteristics. A finite element method has confirmed that the diminution of c/a ratio under this tip pressure explains the observed phase transition of the electron density of states in the film.

Keywords: metal-insulator transition; V2O3 thin films; atomic force microscopy; focused ion beam

Domains: Physics [physics]; Condensed Matter [cond-mat]; Strongly Correlated Electrons [cond-mat.str-el]

Natalia Alyabyeva, Joe Sakai, M. Bavencoffe, J. Wolfman, P. Limelette, et al.. Metal-insulator transition in V 2 O 3 thin film caused by tip-induced strain. Applied Physics Letters, 2018, 113 (24), pp.241603. ⟨10.1063/1.5063712⟩. ⟨hal-02014824⟩