A method for enhancing controllability with adding links in directed networks

In this paper a method to enhance controllability of directed network by adding links is proposed. The adding strategy is based on node degree ratio. Numerical simulation on two network models demonstrates that this method is more effective in enhancing controllability than random adding links method. The effectiveness of this method lies in reducing the degree heterogeneity of network, which is helpful to enhance the controllability of network. We expect our research provide an effective and practical method to enhance the controllability of directed networks.