Nanoparticle-based all-optical sensors
The present invention provides a sensor that includes an optical device as a support for a thin film formed by a matrix containing resonant nanoparticles. The nanoparticles may be optically coupled to the optical device by virtue of the geometry of placement of the thin film. Further, the namoparticles are adapted to resonantly enhance the spectral signature of analytes located near the surfaces of the nanoparticles. Thus, via the nanoparticles, the optical device is addressable so as to detect a measurable property of a sample in contact with the sensor. The sensors include chemical sensors and thermal sensors. The optical devices include reflective devices and waveguide devices. Still further, the nanoparticles include solid metal particles and metal nanoshells. Yet further, the nanoparticles may be part of a nano-structure that further includes nanotubes.
1 . A sensor comprising:
an optical device; and
a thin film supported by said device, said thin film comprising
a matrix; and
a plurality of plasmon resonant particles embedded in said matrix;
wherein said matrix is selected from the group consisting of a transparent matrix, a Raman-active matrix, a semipermeable matrix, a mesoporous matrix, an inorganic oxide, a polymer, a material selected so as to control the maximum wavelength of the resonance of said resonant particles, and combinations thereof.