Transformation from plasmon-induced transparence to -induced absorption through the control of coupling strength in metal-insulator-metal structure.

Photonic structures created by coupling a narrow resonance to a broad resonance can significantly improve the sensitivity of optical sensors. We investigated a planar metal-insulator-metal (MIM) multilayered structure using attenuated total reflection to couple surface plasmon polaritons with the waveguide (WG) mode. A plasmon-induced transparency (PIT) to plasmon-induced adsorption (PIA) transformation was realized by controlling the coupling strength between the incident light and the WG mode. The results indicated that PIT and PIA have differing coupling strength and reflectance phase at surface plasmon resonance. Moreover, Fano resonance was realized by adjusting the center of the absorption band of the WG mode.