The present application relates to semiconductor photodetectors, in particular to a silicon carbide-based UV-visible-NIR full-spectrum-responsive photodetector and a method for fabricating the same. The photodetector includes a silicon carbide substrate, and metal counter electrodes and a surface plasmon polariton nanostructure arranged thereon. The silicon carbide substrate and the metal counter electrodes constitute a metal-semiconductor-metal photodetector with coplanar electrodes. When the ultraviolet light is input, free carriers directly generated in silicon carbide are collected by an external circuit to generate electrical signals. When the visible light is input, hot carriers generated in the surface plasmon polariton nanostructure tunnel into the silicon carbide semiconductor to become free carriers to generate electrical signals.

Methods, systems, and devices are disclosed for photoconductive switch package configurations. In some aspects, a photoconductive switch package includes of a wide bandgap photoconductive material (e.g., GaN, ZnO, diamond, AlN, SiC, BN, etc.), a source for energetic photons (e.g., a laser), a mechanism to couple the laser into the switch, and a mechanism for high voltage to enter and leave the switch package. In some implementations, the disclosed photoconductive switch packages can be configured as a three terminal device, e.g., similar to transistors, with one of the terminals being laser input or the voltage input to the laser system.

Methods, systems, and devices are disclosed for photoconductive switch package configurations. In some aspects, a photoconductive switch package includes of a wide bandgap photoconductive material (e.g., GaN, ZnO, diamond, AlN, SiC, BN, etc.), a source for energetic photons (e.g., a laser), a mechanism to couple the laser into the switch, and a mechanism for high voltage to enter and leave the switch package. In some implementations, the disclosed photoconductive switch packages can be configured as a three terminal device, e.g., similar to transistors, with one of the terminals being laser input or the voltage input to the laser system.

A photoconductive transducer intended to generate or detect waves in the terahertz frequency domain or in the picosecond pulse domain is provided. The transducer comprises a three-dimensional structure that includes, in this order, a first planar electrode, an array of nano-columns embedded in a layer of resist and a second planar electrode parallel to the first planar electrode. The design of the transducer increases the optical-to-terahertz conversion efficiency by means of photonic and plasmonic resonances and by means of high and homogeneous electric fields. The height of the nano-columns as well as the thickness of the resist range between 100 nanometres and 400 nanometres. The width of the nano-columns is between 100 nanometres and 400 nanometres, the distance between two adjacent nano-columns is between 300 nanometres and 500 nanometres, the nano-columns are made of a III-V semiconductor. The second electrode is transparent, so as to allow the transmission of a laser source towards the photo-absorbing nano-columns.

A solid-state component responds to electromagnetic radiation and may be used as a photovoltaic element, as a photoelectric sensor, as a photocatalyst, or as a power store. The solid-state component has asymmetrical electrodes which face each other and are electron-conductively connected to each other by a semiconductor material and a coating in such a way that an open terminal voltage of 1.8 volts or even more is achieved by acting electromagnetic radiation.

In an illuminance sensor, a slow axis of a first quarter-wave plate has a relation of +45° or −45° in regard to a polarization direction of a first linear polarization plate; a relation of a slow axis of a first portion of a second quarter-wave plate in regard to a polarization direction of a second linear polarization plate is the same with relation of the slow axis of the first quarter-wave plate in regard to the polarization direction of the first linear polarization plate, that is, +45° or −45°; and a relation of a slow axis of a second portion of the second quarter plate in regard to the polarization direction of the second linear polarization plate is −45° or +45° that is opposite in sign to the relation of the slow axis of the first quarter-plate in regard to the polarization direction of the first linear polarization plate.

In an illuminance sensor, a slow axis of a first quarter-wave plate has a relation of +45° or −45° in regard to a polarization direction of a first linear polarization plate; a relation of a slow axis of a first portion of a second quarter-wave plate in regard to a polarization direction of a second linear polarization plate is the same with relation of the slow axis of the first quarter-wave plate in regard to the polarization direction of the first linear polarization plate, that is, +45° or −45°; and a relation of a slow axis of a second portion of the second quarter plate in regard to the polarization direction of the second linear polarization plate is −45° or +45° that is opposite in sign to the relation of the slow axis of the first quarter-plate in regard to the polarization direction of the first linear polarization plate.

Disclosed is a method for synthesizing single crystalline molybdenum disulfide via a hydrothermal process that minimizes or eliminates carbon byproducts. The method involves providing two components, including a source of molybdenum and a mineralizer solution, to an inert reaction vessel, heating one zone sufficiently to dissolve the source of molybdenum in the mineralizer solution, and heating a second zone to a lower temperature to allow thermal transport to drive the dissolved material to the second zone, and then precipitate MoS.sub.2 on a seed crystal.

Disclosed is a method for synthesizing single crystalline molybdenum disulfide via a hydrothermal process that minimizes or eliminates carbon byproducts. The method involves providing two components, including a source of molybdenum and a mineralizer solution, to an inert reaction vessel, heating one zone sufficiently to dissolve the source of molybdenum in the mineralizer solution, and heating a second zone to a lower temperature to allow thermal transport to drive the dissolved material to the second zone, and then precipitate MoS.sub.2 on a seed crystal.

An antenna electrode including a first electrode that includes a core and a first conductive surface; a second electrode that includes a second conductive surface; and an electrical tunnel junction between the first conductive surface and the second conductive surface, the tunnel junction having a gap width greater than about 0.1 nm and less than about 10 nm.