Abstract
The dynamical parametric encirclement around a second-order exceptional point (EP) enables the time-asymmetric nonadiabatic evolution of light, which follows the chirality of the underlying system. Such light dynamics in the presence of multiple EPs and the corresponding chiral aspect is yet to be explored. In this Letter, we report a gain-loss assisted four-mode-supported optical waveguide that hosts a parameter space to dynamically encircle multiple EPs. In the presence of multiple EPs, we establish a unique nonadiabatic behavior of light, where beyond the chiral aspect of the system, light is switched to a particular mode, irrespective of the choice of the input mode. Proposed scheme certainly opens a step-forward approach in light manipulation to facilitate next-generation integrated photonic systems. (C) 2020 Optical Society of America