Application of Airy Function Approach to Model Electron Tunneling in Graphene Nanoribbon-Based P-N Junction Diodes

Electron transmittance in a graphene nanoribbon (GNR)-based p+-n+ junction is modeled by employing an Airy function approach. An analytical expression of the transmittance is given and electron tunneling currents in the GNR-based p+-n+ junction are also calculated. It is found that the tunneling current obtained by using the Airy function approach is higher than that under the WKB approach for narrow ribbons. For wider ribbons, the calculated tunneling current under the Airy function approach goes to that under the WKB approach. Moreover, curves of tunneling current versus ribbon width have peak currents and the peak current shifts to narrower ribbon as the electric field in the depletion region increases.