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Growth and Electrostatic/chemical Properties of Metal/LaAlO3/SrTiO3 Heterostructures
Published on: February 8, 2018
Crystal-facet-dependent metallization in electrolyte-gated rutile TiO2 single crystals
Thomas D Schladt1, Tanja Graf, Nagaphani B Aetukuri
1IBM Almaden Research Center , San Jose, California 95120, United States.
Abstract:
The electric-field-induced metallization of insulating oxides is a powerful means of exploring and creating exotic electronic states. Here we show by the use of ionic liquid gating that two distinct facets of rutile TiO2, namely, (101) and (001), show clear evidence of metallization, with a disorder-induced metal-insulator transition at low temperatures, whereas two other facets, (110) and (100), show no substantial effects. This facet-dependent metallization can be correlated with the surface energy of the respective crystal facet and, thus, is consistent with oxygen vacancy formation and diffusion that results from the electric fields generated within the electric double layers at the ionic liquid/TiO2 interface. These effects take place at even relatively modest gate voltages.
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