Study of Localized Modes in Hybrid Plasmonic Waveguide Arrays with Complex Disorder

The study of behavior of electromagnetic waves in disordered photonic systems and the resulting localization phenomena have attracted great interest in the past three decades or so [see e.g. D. S. Wiersma, Nat. Photon. 7, 188-196 (2013)]. Previously we have studied the relationship between disorder strength and mode localization in disordered quasi-one-dimensional hybrid plasmonic rectangular waveguide arrays when the locations of the waveguides are perturbed from a periodic configuration [Hashemizad et al., Opt. Express 33, 5486-5498 (2025)]. In this study, complex disorder is introduced to the array by randomly perturbing the widths of the waveguides or by introducing disorder to both the waveguide widths and the locations of the waveguides. Coupled mode theory with nearest-neighbor coupling is used to find array modes, and localization of modes is measured using both effective mode area and variance in intensity. We analyze how the localization of modes relates to the degree and kind of disorder introduced for different array sizes.