The Nonlinear Electronic Transport in Multilayer Graphene on Silicon-on-Insulator Substrates

We conduct a study on the superlinear transport of multilayer graphene channels that partially or completely locate on silicon which is pre-etched by inductively coupled plasma (ICP). By fabricating a multilayer-graphene field-effect transistor on a Si/SiO_2 substrate, we obtain that the superlinearity results from the interaction between the multilayer graphene sheet and the ICP-etched silicon. In addition, the observed superlinear transport of the device is found to be consistent with the prediction of Schwinger's mechanism. In the high bias regime, the values of \alpha increase dramatically from 1.02 to 1.40. The strength of the electric field corresponding to the on-start of electron–hole pair production is calculated to be 5\times10^4 V/m. Our work provides an experimental observation of the nonlinear transport of the multilayer graphene.