OPTICAL SENSOR WITH MULTILAYERED PLASMON STRUCTURE FOR IMPROVED DETECTION OF CHEMICAL GROUPS THROUGH SERS Russian patent published in 2009 - IPC G01N21/65 B82B1/00 

FIELD: physics; measurement.

SUBSTANCE: invention pertains to measurement techniques. Invented are an optical sensor and a method of using it with a laser beam for stimulating visible light and a detector based on Raman spectroscopy, for detecting chemical groups in an analyte, deposited on the sensor. The sensor comprises a substrate, plasmon-resonance mirror, formed on the sensitive surface of the substrate, a layer of plasmon-resonance particles, put on top of the mirror, and a layer of optically transparent dielectric of thickness 2-40 nm, which separates the mirror and the layer of particles. The layer of particles is formed by a periodic matrix of plasmon-resonance particles, with (i) a coating, capable of bonding analyte molecules, (ii) essentially uniform dimensions and shapes of particles in a chosen range of dimensions 50-200 nm and (iii) regular periodic distance between particles, less than the wavelength of the stimulation laser beam. The device can detect an analyte with amplification factor of up to 10¹²-10¹⁴, i.e. detection of separate molecules of the analyte.

EFFECT: increased sensitivity of analysis.

16 cl, 16 dwg