Asymmetrical splitting in the spectrum of stochastic radiation scattered by non-Hermitian materials having PT symmetry

Abstract

The scattering of partially coherent radiation by a localized continuous material having parity-time ($\mathcal{PT}$) symmetry is considered under the formalism of classical coherence theory and the assumption that the Born approximation is valid. Our results suggest that the correlation-induced spectral changes are strongly dependent upon the gain and loss properties of the material. In particular, the center frequency of the scattered radiation undergoes a discontinuity as a function of the non-Hermitian parameter characterizing the physical properties of the material. The physical reason behind this abrupt behavior is that the $\mathcal{PT}$ symmetry induces the creation of two asymmetrical frequency bands inside the original Hermitian spectrum. We describe how this splitting occurs and offer possibilities to dynamically characterize the scattered spectrum.