▎ 摘　　要

We utilize the relation between soliton solutions of the modified Kortweg-de Vries (mKdV) and the combined mKdV-KdV equation and the Dirac equation to construct electrostatic fields which yield exact zero-energy states in graphene. The examples considered here are fairly general and it has also been shown that some of these examples reproduce the previously known results when parameters are chosen suitably. Copyright (C) EPLA, 2015