Development of hybrid optical microcavities for plasmonic laser and improving biodetection

High quality factor microcavities can serve as a good platform for microlaser, label free biosensor, and fundamental physics study due to its high circulating power. This thesis mainly investigates possibilities for developing Plasmonic nanoparticles and polymer thin film coating microcavities, and demonstrating the optical interaction between optical filed and Plasmonic nanoparticles. A new type of upconversion microlaser based on two photon upconversion of gold nanorods was invented. Performances such as threshold power of the new type laser were demonstrated and optimized. Besides, this thesis has also demonstrated improved performances of label-free biosensor based on microcavities by combining the kinetics constants or varying quality factors of microcavities which were used for detection.;In this thesis, it is first demonstrated the possibilities of permanently coating gold nanoparticles and polydimethylmethacrylate (PMMA, M.W. 35,000) thin film on microcavities with quality factor over than 107. The quality factor was studies both theoretically and experimentally, proving materials loss was the main loss mechanisms. Then low threshold Plasmonic upconversion microlaser is demonstrated where Plasmonic resonance of gold nanorods overlaps with optical resonance of microcavities. The Plasmonic interaction between optical field and gold nanorods are investigated theoretically using 3-D FDTD (Finite Domain Time Domain) simulations. Finally this thesis shows improved performances of label-free biosensor based on resonant shift method of microcavitie.