Figure 3
From: Mechanical writing of n-type conductive layers on the SrTiO3 surface in nanoscale

Transport properties of the conductive layer.
(a) The dependence of the conductivity on temperature. (b) The response of the conductivity to the exposure of oxygen gas. (c) The surface conductivity tuned by back gate voltage. (d) The source-drain current as a function of the gate voltage. The red curves in (a), (b) and (d) are fitting results.