Surface Plasmon Induced Tunable Bistability and Optical Beam Steering

Abstract

The field of surface plasmon has gained immense popularity owing to its electric field enhancement capacity in the surface sensitivity for several spectroscopic measurements including Raman scattering, fluorescence, second harmonic generation (SHG) etc. The versatility of surface plasmon resonance (SPR) phenomenon has attracted intensive scientific interest in the recent years on accounts of its immense practical applications in the field of molecular adsorption, immunoassary, data interpretation, SHG, optical parametric generation, spectroscopy, solar cells, genetic engineering, high contrast SPR microscopy or imaging, mass spectrometry (MS), functional proteomic screening, characterization of enzyme inhibitors, immunosensing etc. Over the last two decades, it has also attracted great attention, experimentally and theoretically, due to the real time optical sensing of physical, chemical and biological properties of materials. The sensitivity of SPR sensing techniques can further be increased by employing the benefits of long-range surface plasmon resonance (LRSP) phenomenon. LRSP possess advantages over the conventional surface plasmons, in terms of higher surface electric field strengths, longer surface propagation length, and narrower angular resonance curves. Further survey on LRSP resonance phenomenon, reveal its vital role in the field of enhancement of optical beam shifts on total internal reflection. It also plays a prime role in all-optical integrated devices where optical bistability can be achieved through excitation of nonlinear surface waves (NSWs) at a kerr nonlinear dielectric-metal interface in a Kretschmann-Raether or Otto configuration. With these applications of LRSP resonance phenomenon, this thesis aims at developing new concepts to generate optical beam steering, low threshold optical bistability and bistable beam shifts using this phenomenon.