1263 results about "Plasmon" patented technology

Surface enhanced Raman Scattering (SERS) and related modalities offer greatly enhanced sensitivity and selectivity for detection of molecular species through the excitation of plasmon modes and their coupling to molecular vibrational modes. One of the chief obstacles to widespread application is the availability of suitable nanostructured materials that exhibit strong enhancement of Raman scattering, are inexpensive to fabricate, and are reproducible. I describe nanostructured surfaces for SERS and other photonic sensing that use semiconductor and metal surfaces fabricated using femtosecond laser processing. A noble metal film (e.g., silver or gold) is evaporated onto the resulting nanostructured surfaces for use as a substrate for SERS. These surfaces are inexpensive to produce and can have their statistical properties precisely tailored by varying the laser processing. Surfaces can be readily micropatterned and both stochastic and self-organized structures can be fabricated. This material has application to a variety of genomic, proteomic, and biosensing applications including label free applications including binding detection. Using this material, monolithic or arrayed substrates can be designed. Substrates for cell culture and microlabs incorporating microfluidics and electrochemical processing can be fabricated as well. Laser processing can be used to form channels in the substrate or a material sandwiched onto it in order to introduce reagents and drive chemical reactions. The substrate can be fabricated so application of an electric potential enables separation of materials by electrophoresis or electro-osmosis.

The invention provides new types of plasmon-driven growth mechanism for silver nanostructures involving the fusion of triangular nanoprisms. This mechanism, which is plasmon excitation-driven and highly cooperative, produces bimodal particle size distributions. In these methods, the growth process can be selectively switched between bimodal and unimodal distributions using dual beam illumination of the nanoparticles. This type of cooperative photo-control over nanostructure growth enables synthesis of monodisperse nanoprisms with a preselected edge length in the 30–120 nm range simply by using one beam to turn off bimodal growth and the other (varied over the 450–700 nm range) for controlling particle size.