Propagation of Partially Coherent Light in non-Hermitian Lattices
Abstract
Band theory for partially coherent light is introduced by using the formalism of second-order classical coherence theory under paraxial approximation. It is demonstrated that the cross-spectral density function, describing correlations between pairs of points in the field, can have bands and gaps and form a correlation band structure. The propagation of a partially coherent beam in non-Hermitian periodic structures is considered to elucidate the interplay between the degree of coherence and the gain/loss present in the lattice. We apply the formalism to study partially coherent Bloch oscillations in lattices having parity-time symmetry and demonstrate that the oscillations can be sustained in such media but they are strongly dependent upon the spatial correlations of the beam. A transition between breathing and oscillating modes is shown to be induced by the degree of spatial coherence.
Keywords
Cite
@article{arxiv.2207.11086,
title = {Propagation of Partially Coherent Light in non-Hermitian Lattices},
author = {P. A. Brandão and J. C. A. Rocha},
journal= {arXiv preprint arXiv:2207.11086},
year = {2022}
}