Details

Autor(en) / Beteiligte

• Ramirez, Juan Gabriel
• Saerbeck, Thomas
• Wang, Siming
• Trastoy, J.
• Malnou, M.
• Lesueur, J.
• Crocombette, Jean-Paul
• Villegas, Javier E.
• Schuller, Ivan K.

Titel

Effect of disorder on the metal-insulator transition of vanadium oxides: Local versus global effects

Ist Teil von

• Physical review. B, Condensed matter and materials physics, 2015-05, Vol.91 (20), Article 205123

Ort / Verlag

United States: American Physical Society

Erscheinungsjahr

2015

Quelle

PROLA - Physical Review Online Archive

Beschreibungen/Notizen

• In this paper we investigate the effect of disorder on highly correlated electron systems, which exhibit metal-insulator transition (MIT) and structural-phase transition (SPT). We show that the effect of ion irradiation is strikingly different between V sub(2)O sub(3) and VO sub(2), two otherwise similar materials. Upon irradiation, the MIT and SPT temperatures in V sub(2)O sub(3) decrease drastically at low absolute dosages, much lower than for VO sub(2). At a low threshold dose, the insulating state of V sub(2)O sub(3) drastically collapses into a metallic state. Contrary to this, irradiation of VO sub(2) leads to a much milder reduction of the MIT and SPT temperatures and to a weak, gradual decrease of the insulating state resistivity not suppressed even at one order of magnitude higher doses than the V sub(2)O sub(3) threshold. These major differences imply that the phase transition in V sub(2)O sub(3) arises from global (rather than local as in VO sub(2)) physical mechanisms that are extremely sensitive to disorder. This shows that the MIT and SPT may have substantially different physical origins in different systems, with the consequent major implications for theoretical descriptions of the MIT in highly correlated electron systems.