Nonohmic Behavior in Near-Stoichiometric Rutile (TiO2)

Abstract

Experimental observations of the isothermal current‐voltage relationships in rutile (TiO₂) over the temperature range 632°–908°C have shown that currents in excess of ohmic currents can be drawn through small, single crystals of near‐stoichiometric composition. These currents have been identified as space‐charge‐limited currents analogous to those observed in the case of a vacuum diode. An increase in the ambient specimen temperature had the effect of displacing the potential for transition from ohmic to non‐ohmic behavior to greater values so that, at 908°C, near‐stoichiometric rutile exhibited only ohmic currents even at the largest fields employed.