Bicyclic signed digraphs with maximal energy

摘要

The energy of a digraph (sidigraph) is defined as the sum of absolute values of real parts of its eigenvalues. Monsalve and Rada (2016) determined the bicyclic digraphs with maximal energy among the set of all bicyclic digraphs with fixed order. In this paper, we find the bicyclic sidigraphs with maximal energy over the set of all bicyclic sidigraphs with fixed order. We also construct few families of non-cospectral equienergetic bicyclic sidigraphs.