Effects of Dipole and Quadrupole Modes on the Switchable Total Transmission and Reflection in an Array of Rectangular Silver Prisms

Using an array of rectangular silver prisms, we numerically demonstrated that dose to 100% transmission and reflection of the electromagnetic wave can be switched by slightly changing the incident wavelengths of less than 10 nm. The calculations showed that the resonance wavelengths are associated with the coherent dipole coupling among nanoparticles, and similar phenomena can also be achieved, when the quadrupole mode of the metal nanoparticles is excited. While the change from total transmission to total reflection can be obtained relatively easier when the dipole mode is excited, the difference of the resonance wavelengths between the total transmission and reflection is larger. At the resonance wavelength of quadrupole excitation, the change between the total transmission and the reflection is very sharp and shows a Fano-shaped spectral profile; however, achieving; close to 100% transmission and reflection is challenging. We studied the effects of prism width, height, and interparticle distance on the resonance wavelength and the efficiencies of the total transmission and reflection. The mechanisms leading to the total transmission and reflection were also investigated. The calculated data can provide guidance in designing optical devices with effectively switchable transmission and reflection.