Abstract
Systems with non-Hermitian Hamiltonians, especially those exhibiting
parity-time ( PT ) symmetry, are of particular interest as they can
describe physical open systems with balanced loss into and gain from the
environment. In this context, the study of eigenvalue locations and the
corresponding phase transitions as a function of the degree of
non-Hermiticity γ is accomplished hereby using feedback theory.
This approach provides insight about the behavior of these systems and
allows generalization of the results for higher-order ones. The proposed
ideas are analyzed in detail for a class of coupled resonant circuit
chains.