Optical nonreciprocity in multilayer nanoisland systems of [Ag–Al₂O₃] _N

Abstract

Abstract We study the effect of optical nonreciprocity in [Ag–Al 2 O 3 ] N multilayer structures. The percolation threshold for Ag films was found to be d ∗ ≈ 2 nm . An anomalously large optical nonreciprocity effect was found in the structures with Ag island layers. This effect appeared as a change in the reflected light polarization ( Δ ω ) when the sample was rotated around its axis from the initial position by 180 ∘ . The effect magnitude reached Δ ω m a x ≈ 7 ∘ . We suggest that a possible mechanism for the optical nonreciprocity effect in these structures can be related to the excitation of localized plasmons in Ag islands. We show that Δ ω essentially depends on the interlayer and intralayer interaction between Ag layers in multilayer structures and is suppressed in the case of strong intralayer and interlayer interaction of plasma oscillations.