Nonlinear transport in ionic liquid gated strontium titanate nanowires

Measurements of the current-voltage (I-V) characteristics of ionic liquid gated nanometer scale channels of strontium titanate have been carried out. At low gate voltages, the I-V characteristics exhibit a large voltage threshold for conduction and a nonlinear power law behavior at all temperatures measured. The source-drain current of these nanowires scales as a power law of the difference between the source-drain voltage and the threshold voltage. The scaling behavior of the I-V characteristic is reminiscent of collective electronic transport through an array of quantum dots. At large gate voltages, the narrow channel acts as a quasi-1D wire whose conductance follows Landauer's formula for multichannel transport.