Effects of Double Interfacial Layers on the Local Field Enhancement Factor and Optical Induced Bistability of a Small Spherical Metal/Dielectric Composites

We propose the way of enhancing the enhancement factor of local field, and increasing the input domain threshold of the optical induced bistability of a spherical metal/dielectric composites within a linear host matrixes. The local field enhancement factor of a metal particles with dielectric core in the presence of double interfacial layers shows two maxima at two different frequencies. By introducing double interfacial layers, we calculate the enhancement factor of the local field. Also using the cubic equation the optical induced bistability of the composite material is calculated. Because of the double interfacial layers, we observe an increasing of the input domain threshold of the optical induced bistability. In comparison with the same composite without interfacial layer and with having single interfacial layer, our finding shows that, introducing additional interfacial layer makes the composite having a better enhancement factor and much better input domain threshold of the optical induced bistability.