Optical Cavity Assisted Surface Plasmon Resonance And Related Novel Phenomena

The coupling effect between surface plasmon resonance and cavity resonance has been found in this paper and discussed in detail.Surface plasmon resonance sensors have been developed greatly during the last decades since they are real-time and unharmful to the tested objectives.Surface plasmon resonance is of high sensitivity in optical response,so is optical resonance in cavity,while these two phenomena are usually studied separately since their mechanisms are different.Multi-layer materials made of metal and dielectric medium were studied in the way of numerical calculations and the interaction between surface plasmon resonance and cavity resonance were found.On one hand,the total thickness of the metal medium plays a critical role in the multi-layer configuration;on the other hand,the interaction between the two resonance can lead to an increase in the number of the resonance peaks in the spectrum or a great sharpening of the single resonance peak.The spectrum reacts significantly differently as the parameters of the cavity change and shows a lot of new and interesting phenomena.What's important is that this interaction can increase the sensitivity of the basic surface plasmon sensors and this method of increasing the sensitivity is analyzed and compared with the former work,the stability,robustness and practicability of this method is discussed.In the research of the interaction between surface plasmon resonance and cavity resonance,the method has been studied to excite the surface plasmon resonance without coupler via multi-layer materials made of metal and dielectric medium alternatively.The characteristic effective medium approximation is introduced as a guideline to design the structure to implement coupler-free surface plasmon resonance,and some conditions where the approximation is valid are introduced.The method of band engineering is also discussed here and the computational results are discussed.The results and conclusions serve to understand the various phenomena related to the metallic surface waves,and to provide new ideas to multi-mode surface plasmon resonance sensors and a much easier method of increasing the sensitivity of the sensors.