Fano effect in a one-dimensional photonic lattice with side-coupled P T-symmetric non-Hermitian defects

We theoretically study the transport properties in a one-dimensional photonic lattice influenced by the presence of side-coupled P T-symmetric non-Hermitian defects. The P T symmetry is manifested as the complex potentials on the defects and the complex defect-lattice couplings, respectively. These two mechanisms are found to induce the Fano effect in the transport processes, with the different characteristics of it. Next, if the complex potentials and defect-lattice couplings co-exist, the Fano effect will be achieved more efficiently. However, further enhancing either of them can weaken the Fano interference seriously. Our findings reveal the physical essence of the Fano effect on the P T-symmetric non-Hermitian defects, and the results can provide insights into the engineering and dynamical control of Fano resonances in non-Hermitian photonic structures.