Abstract: Hyperspectral resonant cavity imaging spectrometers and imaging systems incorporating the resonant cavity spectrometers are provided. The spectrometers include an array of photodetectors based on photosensitive semiconductor nanomembranes disposed between two dielectric spacers, each of the dielectric spacers having a thickness gradient along a lateral direction, such that the resonant cavity height differs for different photodetectors in the array.

Abstract: A solar vapor generator system and method are provided. In some embodiments, the system has near perfect energy conversion efficiency in the process of solar vapor generation below room temperature. Remarkably, when the operation temperature of the system is below that of the surroundings, the total vapor generation will be higher than the upper limit that can be produced by the input solar energy.

Abstract: Hyperspectral resonant cavity imaging spectrometers and imaging systems incorporating the resonant cavity spectrometers are provided. The spectrometers include an array of photodetectors based on photosensitive semiconductor nanomembranes disposed between two dielectric spacers, each of the dielectric spacers having a thickness gradient along a lateral direction, such that the resonant cavity height differs for different photodetectors in the array.

Abstract: A system is provided for advanced health monitoring and diagnosis based on wearable nano-biosensing networks. Nanophotonic and wireless communication technologies are synergistically leveraged to bridge the gap between nano-biosensing technologies and commercial wearable devices. Embodiments of the presently-disclosed system may include: (1) a nanoplasmonic biochip, implanted subcutaneously and built on a flexible substrate; (2) a nanophotonic smart band or wearable device that is able to collect in-vivo signals on-demand and relay them wirelessly to the user's smartphone by means of a secure data transfer; and (3) advanced signal processing techniques implemented on a remote processor to extract relevant data from the received signals and provide a diagnosis in real-time.

Abstract: Structures and methods for Surface-Enhanced Raman Spectroscopy (SERS) are presented. In some embodiments, a SERS structure includes a ground plate with a spacer layer disposed thereon. A first plurality of metallic nanostructures is disposed on the spacer layer such that a portion of the spacer layer is exposed in gaps formed between the nanostructures of the first plurality of metallic nanostructures. In some embodiments, a first metallic layer is annealed to form the first plurality of metallic nanostructures. A second plurality of metallic nanostructures is disposed on the spacer layer in the gaps of the first plurality of metallic nanostructures. In some embodiments, a second metallic layer is annealed to form the second plurality of metallic nanostructures.

Abstract: Disclosed herein are systems and methods for passively cooling water vapor to enable efficient condensation, and methods of making such systems. A passive cooler can include a thermally conductive substrate having a first side and a second side opposite the first side, a coating disposed on at least a portion of the first side of the substrate, and a housing having one or more insulative walls. The insulative walls may define a vapor flow channel from an inlet to an outlet of the housing such that the second side of the substrate is exposed to water vapor flowing through the vapor flow channel.

Abstract: A passive cooler of the disclosure includes a thermal emitter having a substrate and a coating disposed on at least a portion of a first side of the substrate. The cooler has a beam guide made from a material having a high absorption to solar wavelengths and high reflectance at mid-infrared wavelengths. The beam guide is configured such that at least a portion of incident light is acted on by the beam guide before reaching the thermal emitter. In some embodiments, the beam guide has a graded optical index.

Abstract: A system is provided for advanced health monitoring and diagnosis based on wearable nano-biosensing networks. Nanophotonic and wireless communication technologies are synergistically leveraged to bridge the gap between nano-biosensing technologies and commercial wearable devices. Embodiments of the presently-disclosed system may include: (1) a nanoplasmonic biochip, implanted subcutaneously and built on a flexible substrate; (2) a nanophotonic smart band or wearable device that is able to collect in-vivo signals on-demand and relay them wirelessly to the user's smartphone by means of a secure data transfer; and (3) advanced signal processing techniques implemented on a remote processor to extract relevant data from the received signals and provide a diagnosis in real-time.

Abstract: Disclosed herein are systems and methods for passively cooling water vapor to enable efficient condensation, and methods of making such systems. A passive cooler can include a thermally conductive substrate having a first side and a second side opposite the first side, a coating disposed on at least a portion of the first side of the substrate, and a housing having one or more insulative walls. The insulative walls may define a vapor flow channel from an inlet to an outlet of the housing such that the second side of the substrate is exposed to water vapor flowing through the vapor flow channel.

Abstract: Optoelectronic devices that use very thin single-crystalline inorganic semiconductor films as phonon-absorbing layers in combination with non-lattice optical cavities are provided.

Abstract: A solar vapor generator system and method are provided. In some embodiments, the system has near perfect energy conversion efficiency in the process of solar vapor generation below room temperature. Remarkably, when the operation temperature of the system is below that of the surroundings, the total vapor generation will be higher than the upper limit that can be produced by the input solar energy.

Abstract: Optoelectronic devices that use very thin single-crystalline inorganic semiconductor films as phonon-absorbing layers in combination with non-lattice optical cavities are provided.

Abstract: An optical device includes a transparent substrate and a conductive layer disposed over an upper surface of the transparent substrate. The conductive layer defines at least one groove inwardly extending from an upper surface and includes an aperture that is spaced apart from the at least one groove. An interface between the upper surface of the conductive layer and an ambient medium defines an optical branch along which surface plasmon polariton modes are excited in response to at least partially coherent light being received by the optical device.

Abstract: An optical device includes a transparent substrate and a conductive layer disposed over an upper surface of the transparent substrate. The conductive layer defines at least one groove inwardly extending from an upper surface and includes an aperture that is spaced apart from the at least one groove. An interface between the upper surface of the conductive layer and an ambient medium defines an optical branch along which surface plasmon polariton modes are excited in response to at least partially coherent light being received by the optical device.

Abstract: An optical device includes a transparent substrate and a conductive layer disposed over an upper surface of the transparent substrate. The conductive layer defines at least one groove inwardly extending from an upper surface and includes an aperture that is spaced apart from the at least one groove. An interface between the upper surface of the conductive layer and an ambient medium defines an optical branch along which surface plasmon polariton modes are excited in response to at least partially coherent light being received by the optical device.

Abstract: The invention discloses methods for making photonic bandgap structures and photonic bandgap structures made by those processes. In one embodiment, the photonic bandgap structure is flexible. In another photonic bandgap structure, the structure has a graded, periodic grating. One embodiment of a method according to the present invention comprises the steps of preparing a pre-polymer mixture, positioning that mixture between two slides, exposing the mixture to electromagnetic radiation, curing the mixture, and discarding at least one of the slides. In another embodiment of the method, the pre-polymer mixture is exposed to the electromagnetic radiation through a prism. In one embodiment of the method, the pre-polymer mixture is exposed to the electromagnetic radiation through a lens. In one embodiment of the invention, the photonic bandgap structure is used as a filter in a multispectral imaging device comprising a imaging device, the filter, a processor, and an electronic image storage device.

Abstract: An optical device includes a transparent substrate and a conductive layer disposed over an upper surface of the transparent substrate. The conductive layer defines at least one groove inwardly extending from an upper surface and includes an aperture that is spaced apart from the at least one groove. An interface between the upper surface of the conductive layer and an ambient medium defines an optical branch along which surface plasmon polariton modes are excited in response to at least partially coherent light being received by the optical device.

Abstract: An optical device includes first and second optical branches. The first optical branch is formed at an interface between a first substrate and a second substrate, and the second optical branch is formed at an interface between the second substrate and an ambient medium. The second substrate defines first and second spaced apart slits that are each coupled to the first and second optical branches. The first slit is configured to receive at least partially coherent light from a light source and in response excite at least one surface plasmon polariton mode in each of the first and second optical branches. The second slit is configured to combine the surface plasmon polariton modes received from the first and second optical branches and emit scattered light into at least one of the first substrate and the ambient medium.

Abstract: A slow light system includes a substrate and a metal layer formed thereon, the metal layer having a graded grating structure formed at a surface thereof, wherein the grating depth of the grating structure is sized such that surface-plasmon polariton dispersion behavior of the grating structure differs at different respective locations along the grating structure. Different wavelengths of incident light waves can be slowed at the respective locations along the grating structure.

Abstract: An optical device includes first and second optical branches. The first optical branch is formed at an interface between a first substrate and a second substrate, and the second optical branch is formed at an interface between the second substrate and an ambient medium. The second substrate defines first and second spaced apart slits that are each coupled to the first and second optical branches. The first slit is configured to receive at least partially coherent light from a light source and in response excite at least one surface plasmon polariton mode in each of the first and second optical branches. The second slit is configured to combine the surface plasmon polariton modes received from the first and second optical branches and emit scattered light into at least one of the first substrate and the ambient medium.