Abstract: A gas sensor comprising: a substrate; a grating array disposed on top of the substrate and comprising grates; and voids defined by the grates and configured to confine gas molecules for absorption of light and analysis. A method of gas sensing comprising: generating first light; converting the first light into second light using grates of a grating array; resonating the second light within the grating array; confining gas molecules in voids defined by the grates; and causing the gas molecules to absorb the second light within the voids.

Abstract: A method of manufacturing a lead salt thin film on a substrate by seeding a substrate with a lead salt solution (e.g., PbSe, PbS, or PbTe) to form a seeded substrate comprising lead salt seed crystals, and growing the lead salt thin film upon the substrate by exposing the seeded substrate to a chemical bath comprising the lead salt solution at a predetermined growth temperature. A lead salt thin film manufactured by the process. A photonic crystal microchip comprising the lead salt thin film. A gas sensing device comprising a diode laser, a mid-infrared photodetector, and the photonic crystal microchip. A method of detecting a hydrocarbon gas, comprising exposing a gas sample to the gas sensing device, and determining the content of hydrocarbon gases in the gas sample.

Abstract: Tracking patient compliance with treatment protocols is an important aspect of delivering high quality healthcare. A system for tracking compliance with protocols that include the periodic consumption of oral medication includes a mobile computing device and a pill tracking dispenser. The mobile computing device includes an application program configured to record the periodic consumption of oral medication by the patient. The pill tracking dispenser can be connected to the mobile computing device through a wireless network. The pill tracking dispenser is configured to report to the mobile computing device the number of times the oral medication is consumed by the patient.

Abstract: An apparatus comprises: a photonic cavity; a substrate comprising a waveguide layer, wherein the waveguide layer comprises waveguides configured to direct light towards the photonic cavity; and a wafer comprising: a top side, and a nanowire array affixed to the top side. A method of performing a surface-enhanced Raman scattering (SERS) analysis, the method comprises: directing, using a waveguide layer of a SERS device, an incident light towards a photonic cavity of the SERS device; permitting, using the photonic cavity, a fluid to flow freely into and out of the SERS device; causing, within the photonic cavity, an interaction among the incident light, the fluid, and a nanowire array of the SERS device to create scattered light; converting the scattered light into an electrical signal; and analyzing the electrical signal to determine whether a contaminant exists in the fluid.

Abstract: A gas sensor comprising: a substrate; a grating array disposed on top of the substrate and comprising grates; and voids defined by the grates and configured to confine gas molecules for absorption of light and analysis. A method of gas sensing comprising: generating first light; converting the first light into second light using grates of a grating array; resonating the second light within the grating array; confining gas molecules in voids defined by the grates; and causing the gas molecules to absorb the second light within the voids.

Abstract: An apparatus comprises: a photonic cavity; a substrate comprising a waveguide layer, wherein the waveguide layer comprises waveguides configured to direct light towards the photonic cavity; and a wafer comprising: a top side, and a nanowire array affixed to the top side. A method of performing a surface-enhanced Raman scattering (SERS) analysis, the method comprises: directing, using a waveguide layer of a SERS device, an incident light towards a photonic cavity of the SERS device; permitting, using the photonic cavity, a fluid to flow freely into and out of the SERS device; causing, within the photonic cavity, an interaction among the incident light, the fluid, and a nanowire array of the SERS device to create scattered light; converting the scattered light into an electrical signal; and analyzing the electrical signal to determine whether a contaminant exists in the fluid.

Abstract: Disclosed is at least one embodiment of an infrared (IR) photovoltaic (PV) detector, comprising a IV-VI Lead (Pb)-salt layer disposed on a substrate and a charge-separation-junction (CSJ) structure associated with the IV-VI Pb-salt layer, wherein the CSJ structure comprises a plurality of element areas disposed upon or within the IV-VI Pb-salt layer, wherein the plurality of element areas are spaced apart from each other. Each element area may be connected to a first Ohmic contact thereby forming a plurality of interconnected first Ohmic contacts, and a second Ohmic contact may be disposed upon a portion of the IV-VI Pb-salt layer. In another non-limiting embodiment, a PV detector, comprising a heterojunction region that comprises at least one IV-VI Pb-salt material layer coupled to at least one non-Pb-salt layer, wherein the at least one IV-VI Pb-salt layer and the at least one non-Pb-salt layer form a p-n junction or Schottky junction with a type II band gap alignment.

Abstract: Disclosed is at least one embodiment of an infrared (IR) photovoltaic (PV) detector, comprising a IV-VI Lead (Pb)-salt layer disposed on a substrate and a charge-separation-junction (CSJ) structure associated with the IV-VI Pb-salt layer, wherein the CSJ structure comprises a plurality of element areas disposed upon or within the IV-VI Pb-salt layer, wherein the plurality of element areas are spaced apart from each other. Each element area may be connected to a first Ohmic contact thereby forming a plurality of interconnected first Ohmic contacts, and a second Ohmic contact may be disposed upon a portion of the IV-VI Pb-salt layer. In another non-limiting embodiment, a PV detector, comprising a heterojunction region that comprises at least one IV-VI Pb-salt material layer coupled to at least one non-Pb-salt layer, wherein the at least one IV-VI Pb-salt layer and the at least one non-Pb-salt layer form a p-n junction or Schottky junction with a type II band gap alignment.

Abstract: Disclosed is at least one embodiment of an infrared (IR) photovoltaic (PV) detector, comprising a IV-VI Lead (Pb)-salt layer disposed on a substrate and a charge-separation-junction (CSJ) structure associated with the IV-VI Pb-salt layer, wherein the CSJ structure comprises a plurality of element areas disposed upon or within the IV-VI Pb-salt layer, wherein the plurality of element areas are spaced apart from each other. Each element area may be connected to a first Ohmic contact thereby forming a plurality of interconnected first Ohmic contacts, and a second Ohmic contact may be disposed upon a portion of the IV-VI Pb-salt layer. In another non-limiting embodiment, a PV detector, comprising a heterojunction region that comprises at least one IV-VI Pb-salt material layer coupled to at least one non-Pb-salt layer, wherein the at least one IV-VI Pb-salt layer and the at least one non-Pb-salt layer form a p-n junction or Schottky junction with a type II band gap alignment.

Abstract: The disclosure describes methods for preparing lead salt materials which are sensitive to the mid-infrared spectrum which can be used to manufacture high-uniformity, high-detectivity, polycrystalline lead salt photoconductive and photovoltaic photodetectors.