Highly-dispersive unidirectional reflectionless phenomenon based on high-order plasmon resonance in metamaterials

In this work, we design a structure of metamaterials that consists of double sliver-ring resonators, in which highly-dispersive unidirectional reflectionlessness and absorption are achieved based on high-order plasmon resonance. Reflections of +z and -z directions at 461.34 THz (456.68 THz) are ∼0 (0.82) and ∼0.85 (0) when the distance d=222.9 nm (259.8 nm), respectively. High absorption of ∼0.97 and the quality factor of ∼435 can be obtained in the loss metal structure at room temperature. What's more, unidirectional reflectionlessness is investigated at low temperature.