PT -symmetry-induced wave confinement and guiding in ε -near-zero metamaterials

摘要: Inspired by the parity-time symmetry concept, we show that a judicious spatial modulation of gain and loss in $\ensuremath{\epsilon}$-near-zero metamaterials can induce propagation exponentially bound interface modes characterized zero attenuation. With specific reference to bilayer configuration, via analytical studies parametrization dispersion equation, this waveguiding mechanism be sustained presence moderate gain/loss levels, it becomes leaky (i.e., radiative) below threshold. Moreover, explore possible rod-based metamaterial implementation, based on realistic material constituents, which captures essential features mechanism, good agreement with our theoretical predictions. Our results may open up possibilities for design optical devices reconfigurable nanophotonics platforms.