Abstract: A room temperature nitrogen dioxide gas sensor comprising tin(IV) oxide decorated with gold nanoparticles is described. The tin(IV) oxide may have an average layer thickness of 10-1,000 nm, and is topped with dispersed gold nanoparticles having an average longest dimension of 200-650 nm. The room temperature nitrogen dioxide gas sensor may be used to detect and measure levels of nitrogen dioxide gas at room temperature and at concentrations of 100 ppb-1800 ppm, with a high stability. A method of making the room temperature nitrogen dioxide sensor is also described, and involves sputtering to deposit a tin(IV) oxide layer and a gold layer on a substrate, followed by annealing.

Abstract: A hydrogen gas sensor with a substrate and a zinc oxide nanostructured thin film deposited on the substrate, wherein the zinc oxide nanostructured thin film has a lattice structure with a weight ratio of low binding energy O2? ions to medium binding energy oxygen vacancies in a range of 0.1 to 1.0, and a method of fabricating a gas sensor by thermally oxidizing a metal thin film under low oxygen partial pressure. Various combinations of embodiments of the hydrogen gas sensor and the method of fabricating the gas sensor are provided.

Abstract: A wavelength tunable gain medium with the use of micro-electromechanical system (MEMS) based Fabry-Perot (FP) filter cavity tuning is provided as a tunable laser. The system comprises a laser cavity and a filter cavity for wavelength selection. The laser cavity consists of a gain medium such as a Semiconductor Optical Amplifier (SOA), two collimating lenses and an end reflector. The MEMS-FP filter cavity comprises a fixed reflector and a moveable reflector, controllable by electrostatic force. By moving the MEMS reflector, the wavelength can be tuned by changing the FP filter cavity length. The MEMS FP filter cavity displacement can be tuned discretely with a step voltage, or continuously by using a continuous driving voltage. The driving frequency for continuous tuning can be a resonance frequency or any other frequency of the MEMS structure, and the tuning range can cover different tuning ranges such as 30 nm, 40 nm, and more than 100 nm.

Abstract: A surface enhanced Raman scattering (SERS) active nanoassembly comprising anisotropically assembled gold nanoparticles in a monolayer double row immobilized on a glass layer is disclosed. The discrete gold nanoparticles are separated by interparticle gaps of 0.5-10 nm that provide hotsites where appropriate excitation creates surface plasmon resonaces and regions of strong and localized electromagnetic fields that enhance Raman signal substantially, 104-1015 fold. An appropriate SERS apparatus comprising the nanoassembly for detecting an analyte is also disclosed. In addition, a method for producing the nanoassembly as well as the application of the nanoassembly or the apparatus comprising the nanoassembly in a method for measuring the SERS signal of an analyte is disclosed.

Abstract: A surface enhanced Raman scattering (SERS) active nanoassembly comprising anisotropically assembled gold nanoparticles in a monolayer double row immobilized on a glass layer is disclosed. The discrete gold nanoparticles are separated by interparticle gaps of 0.5-10 nm that provide hotsites where appropriate excitation creates surface plasmon resonaces and regions of strong and localized electromagnetic fields that enhance Raman signal substantially, 104-1015 fold. An appropriate SERS apparatus comprising the nanoassembly for detecting an analyte is also disclosed. In addition, a method for producing the nanoassembly as well as the application of the nanoassembly or the apparatus comprising the nanoassembly in a method for measuring the SERS signal of an analyte is disclosed.

Abstract: A surface enhanced Raman scattering (SERS) active nanoassembly comprising anisotropically assembled gold nanoparticles in a monolayer double row immobilized on a glass layer is disclosed. The discrete gold nanoparticles are separated by interparticle gaps of 0.5-10 nm that provide hotsites where appropriate excitation creates surface plasmon resonaces and regions of strong and localized electromagnetic fields that enhance Raman signal substantially, 104-1015 fold. An appropriate SERS apparatus comprising the nanoassembly for detecting an analyte is also disclosed. In addition, a method for producing the nanoassembly as well as the application of the nanoassembly or the apparatus comprising the nanoassembly in a method for measuring the SERS signal of an analyte is disclosed.

Abstract: A plasmonic scattering nanomaterial comprising a substrate layer, a metal oxide layer in continuous contact with the substrate layer and silver nanoparticles with a diameter of 25-300 nm deposited on the metal oxide layer is disclosed. The silver nanoparticles have a broad size distribution and interparticle distances such that the silver nanoparticles plasmonically scatter light throughout the metal oxide layer with a near electric field strength of 1-30 V/m when excited by a light source having a wavelength in the range of 300-500 nm and/or 1000-1200 nm. In addition, a method for producing the nanomaterial by sputter deposition is disclosed as well as an appropriate thin film plasmonic solar cell comprising the nanomaterial with a solar efficiency of at least 10%.

Abstract: A plasmonic scattering nanomaterial comprising a substrate layer, a metal oxide layer in continuous contact with the substrate layer and silver nanoparticles with a diameter of 25-300 nm deposited on the metal oxide layer is disclosed. The silver nanoparticles have a broad size distribution and interparticle distances such that the silver nanoparticles plasmonically scatter light throughout the metal oxide layer with a near electric field strength of 1-30 V/m when excited by a light source having a wavelength in the range of 300-500 nm and/or 1000-1200 nm. In addition, a method for producing the nanomaterial by sputter deposition is disclosed as well as an appropriate thin film plasmonic solar cell comprising the nanomaterial with a solar efficiency of at least 10%.

Abstract: A surface enhanced Raman scattering (SERS) active nanoassembly comprising anisotropically assembled gold nanoparticles in a monolayer double row immobilized on a glass layer is disclosed. The discrete gold nanoparticles are separated by interparticle gaps of 0.5-10 nm that provide hotsites where appropriate excitation creates surface plasmon resonaces and regions of strong and localized electromagnetic fields that enhance Raman signal substantially, 104-1015 fold. An appropriate SERS apparatus comprising the nanoassembly for detecting an analyte is also disclosed. In addition, a method for producing the nanoassembly as well as the application of the nanoassembly or the apparatus comprising the nanoassembly in a method for measuring the SERS signal of an analyte is disclosed.

Abstract: A method of preparing silver nanoparticles, including silver nanorings. A zinc oxide thin film is formed initially by direct-current sputtering of a zinc target onto a substrate. A silver thin film is then formed by a similar sputtering technique, of a silver target onto the zinc oxide thin film. After that, the silver thin film is subject to an annealing treatment. The temperature, duration and atmosphere of the annealing treatment can be varied to control the average particle size, average distance between particles (density), particle size distribution of the silver nanoparticles. In at least one embodiment, silver nanoparticles of ring structure are produced.

Abstract: A method of preparing silver nanoparticles, including silver nanorings. A zinc oxide thin film is formed initially by direct-current sputtering of a zinc target onto a substrate. A silver thin film is then formed by a similar sputtering technique, of a silver target onto the zinc oxide thin film. After that, the silver thin film is subject to an annealing treatment. The temperature, duration and atmosphere of the annealing treatment can be varied to control the average particle size, average distance between particles (density), particle size distribution of the silver nanoparticles. In at least one embodiment, silver nanoparticles of ring structure are produced.

Abstract: A plasmonic scattering nanomaterial comprising a substrate layer, a metal oxide layer in continuous contact with the substrate layer and silver nanoparticles with a diameter of 25-300 nm deposited on the metal oxide layer is disclosed. The silver nanoparticles have a broad size distribution and interparticle distances such that the silver nanoparticles plasmonically scatter light throughout the metal oxide layer with a near electric field strength of 1-30 V/m when excited by a light source having a wavelength in the range of 300-500 nm and/or 1000-1200 nm. In addition, a method for producing the nanomaterial by sputter deposition is disclosed as well as an appropriate thin film plasmonic solar cell comprising the nanomaterial with a solar efficiency of at least 10%.

Abstract: A surface enhanced Raman scattering (SERS) active nanoassembly comprising anisotropically assembled gold nanoparticles in a monolayer double row immobilized on a glass layer is disclosed. The discrete gold nanoparticles are separated by interparticle gaps of 0.5-10 nm that provide hotsites where appropriate excitation creates surface plasmon resonaces and regions of strong and localized electromagnetic fields that enhance Raman signal substantially, 104-1015 fold. An appropriate SERS apparatus comprising the nanoassembly for detecting an analyte is also disclosed. In addition, a method for producing the nanoassembly as well as the application of the nanoassembly or the apparatus comprising the nanoassembly in a method for measuring the SERS signal of an analyte is disclosed.

Abstract: A method of preparing silver nanoparticles, including silver nanorings. A zinc oxide thin film is formed initially by direct-current sputtering of a zinc target onto a substrate. A silver thin film is then formed by a similar sputtering technique, of a silver target onto the zinc oxide thin film. After that, the silver thin film is subject to an annealing treatment. The temperature, duration and atmosphere of the annealing treatment can be varied to control the average particle size, average distance between particles (density), particle size distribution of the silver nanoparticles. In at least one embodiment, silver nanoparticles of ring structure are produced.

Abstract: A wavelength tunable gain medium with the use of micro-electromechanical system (MEMS) based Fabry-Perot (FP) filter cavity tuning is provided as a tunable laser. The system comprises a laser cavity and a filter cavity for wavelength selection. The laser cavity consists of a gain medium such as a Semiconductor Optical Amplifier (SOA), two collimating lenses and an end reflector. The MEMS-FP filter cavity comprises a fixed reflector and a moveable reflector, controllable by electrostatic force. By moving the MEMS reflector, the wavelength can be tuned by changing the FP filter cavity length. The MEMS FP filter cavity displacement can be tuned discretely with a step voltage, or continuously by using a continuous driving voltage. The driving frequency for continuous tuning can be a resonance frequency or any other frequency of the MEMS structure, and the tuning range can cover different tuning ranges such as 30 nm, 40 nm, and more than 100 nm.

Abstract: A wavelength tunable gain medium with the use of micro-electromechanical system (MEMS) based Fabry-Perot (FP) filter cavity tuning is provided as a tunable laser. The system comprises a laser cavity and a filter cavity for wavelength selection. The laser cavity consists of a gain medium such as a Semiconductor Optical Amplifier (SOA), two collimating lenses and an end reflector. The MEMS-FP filter cavity comprises a fixed reflector and a moveable reflector, controllable by electrostatic force. By moving the MEMS reflector, the wavelength can be tuned by changing the FP filter cavity length. The MEMS FP filter cavity displacement can be tuned discretely with a step voltage, or continuously by using a continuous driving voltage. The driving frequency for continuous tuning can be a resonance frequency or any other frequency of the MEMS structure, and the tuning range can cover different tuning ranges such as 30 nm, 40 nm, and more than 100 nm.

Abstract: A plasmonic scattering nanomaterial comprising a substrate layer, a metal oxide layer in continuous contact with the substrate layer and silver nanoparticles with a diameter of 25-300 nm deposited on the metal oxide layer is disclosed. The silver nanoparticles have a broad size distribution and interparticle distances such that the silver nanoparticles plasmonically scatter light throughout the metal oxide layer with a near electric field strength of 1-30 V/m when excited by a light source having a wavelength in the range of 300-500 nm and/or 1000-1200 nm. In addition, a method for producing the nanomaterial by sputter deposition is disclosed as well as an appropriate thin film plasmonic solar cell comprising the nanomaterial with a solar efficiency of at least 10%.

Abstract: A method of preparing silver nanoparticles, including silver nanorings. A zinc oxide thin film is formed initially by direct-current sputtering of a zinc target onto a substrate. A silver thin film is then formed by a similar sputtering technique, of a silver target onto the zinc oxide thin film. After that, the silver thin film is subject to an annealing treatment. The temperature, duration and atmosphere of the annealing treatment can be varied to control the average particle size, average distance between particles (density), particle size distribution of the silver nanoparticles. In at least one embodiment, silver nanoparticles of ring structure are produced.

Abstract: A wavelength tunable gain medium with the use of micro-electromechanical system (MEMS) based Fabry-Perot (FP) filter cavity tuning is provided as a tunable laser. The system comprises a laser cavity and a filter cavity for wavelength selection. The laser cavity consists of a gain medium such as a Semiconductor Optical Amplifier (SOA), two collimating lenses and an end reflector. The MEMS-FP filter cavity comprises a fixed reflector and a moveable reflector, controllable by electrostatic force. By moving the MEMS reflector, the wavelength can be tuned by changing the FP filter cavity length. The MEMS FP filter cavity displacement can be tuned discretely with a step voltage, or continuously by using a continuous driving voltage. The driving frequency for continuous tuning can be a resonance frequency or any other frequency of the MEMS structure, and the tuning range can cover different tuning ranges such as 30 nm, 40 nm, and more than 100 nm.