Influence of [formula omitted]-symmetric complex potentials on the decoupling mechanism in quantum transport processes

Abstract

We consider one system in which the terminal dots of a one-dimensional quantum-dot chain couple equally to the left and right leads and study the influence of PT-symmetric complex potentials on the quantum transport process. It is found that in the absence of the complex potentials, remarkable decoupling and antiresonance phenomena are able to co-occur in the transport process. For the chains with odd(even) dots, their even(odd)-numbered molecular states decouple from the leads. Meanwhile, antiresonance occurs at the positions of the even(odd)-numbered eigenenergies of the sub-chains without terminal dots. When the PT-symmetric complex potentials are applied on the terminal dots, the decoupling phenomenon is found to transform into the Fano antiresonance. These results can helpful in understanding the quantum transport modified by the PT symmetry in non-Hermitian discrete systems.