A photodetector having a small form factor and having high detection efficiency with respect to both visible light and infrared rays may include a first electrode, a collector layer on the first electrode, a tunnel barrier layer on the collector layer, a graphene layer on the tunnel barrier layer, an emitter layer on the graphene layer, and a second electrode on the emitter layer. The photodetector may be included in an image sensor. An image sensor may include a substrate, an insulating layer on the substrate, and a plurality of photodetectors on the insulating layer. The photodetectors may be aligned with each other in a direction extending parallel or perpendicular to a top surface of the insulating layer. The photodetector may be included in a LiDAR system.

Systems and methods for perovskite single crystal growth include using a low temperature solution process that employs a temperature gradient in a perovskite solution in a container, also including at least one small perovskite single crystal, and a substrate in the solution upon which substrate a perovskite crystal nucleates and grows, in part due to the temperature gradient in the solution and in part due to a temperature gradient in the substrate. For example, a top portion of the substrate external to the solution may be cooled.

Methods, systems, and devices are disclosed for low noise and high efficiency photoelectric amplification based on cycling excitation process (CEP). In some aspects, a device for amplifying signals of light-induced photocurrent includes an anode connected to a positive terminal of a voltage source; a disordered material layer coupled to the anode, wherein the disordered material layer is structured to have a thickness of 100 nm or less; and a cathode coupled to the disordered material layer and connected to a negative terminal of the voltage source, in which the device is operable to amplify photoexcited carriers based on photon absorption to produce an external quantum efficiency of the device that is at least 100%.

Methods of making a semiconductor layer from nanocrystals are disclosed. A film of nanocrystals capped with a ligand can be deposited onto a substrate; and the nanocrystals can be irradiated with one or more pulses of light. The pulsed light can be used to substantially remove the ligands from the nanocrystals and leave the nanocrystals unsintered or sintered, thereby providing a semiconductor layer. Layered structures comprising these semiconductor layers with an electrode are also disclosed. Devices comprising such layered structures are also disclosed.

A formulation for use in the preferential formation of thin films of a perovskite material AMX 3 with a certain required crystalline structure, wherein said formulation comprises two or more compounds which between them comprise one or more first organic cations A; one or more metalcations M; one or more second cations A′; one or more first anions X and one or more second anions X′.

An optical detector (110) is disclosed. The optical detector (110) comprises: an optical sensor (112), having a substrate (116) and at least one photosensitive layer setup (118) disposed thereon, the photosensitive layer setup (118) having at least one first electrode (120), at least one second electrode (130) and at least one photovoltaic material (140) sandwiched in between the first electrode (120) and the second electrode (130), wherein the photovoltaic material (140) comprises at least one organic material, wherein the first electrode (120) comprises a plurality of first electrode stripes (124) and wherein the second electrode (130) comprises a plurality of second electrode stripes (134), wherein the first electrode stripes (124) and the second electrode stripes (134) intersect such that a matrix (142) of pixels (144) is formed at intersections of the first electrode stripes (124) and the second electrode stripes (134); and at least one readout device (114), the readout device (114) comprising a plurality of electrical measurement devices (154) being connected to the second electrode stripes (134) and a switching device (160) for subsequently connecting the first electrode stripes (124) to the electrical measurement devices (154).

Photovoltaic devices such as solar cells, hybrid solar cell-batteries, and other such devices may include an active layer disposed between two electrodes. The active layer may have perovskite material and other material such as mesoporous material, interfacial layers, thin-coat interfacial layers, and combinations thereof. The perovskite material may be photoactive. The perovskite material may be disposed between two or more other materials in the photovoltaic device. Inclusion of these materials in various arrangements within an active layer of a photovoltaic device may improve device performance. Other materials may be included to further improve device performance, such as, for example: additional perovskites, and additional interfacial layers.

The present disclosure relates to a novel polymer compound and a method for preparing the same. More particularly, the present disclosure relates to a novel conductive low band gap electron donor polymer compound having high photon absorptivity and improved hole mobility, a method for preparing the same and an organic photovoltaic cell containing the same. Since the conductive polymer compound as a low band gap electron donor exhibits high photon absorptivity and superior hole mobility, it can be usefully used as a material for an organic optoelectronic device such as an organic photodiode (OPD), an organic thin-film transistor (OTFT), an organic light-emitting diode (OLED), an organic photovoltaic cell, etc. as well as in the development of a n-type material.

An object of the present invention is to provide a solar cell that is excellent in photoelectric conversion efficiency, suffers little degradation during encapsulation (initial degradation), and has high-temperature durability. The present invention provides a solar cell including: a laminate having an electrode, a counter electrode, and a photoelectric conversion layer disposed between the electrode and the counter electrode; and an encapsulation resin layer covering the counter electrode to encapsulate the laminate, the photoelectric conversion layer including an organic-inorganic perovskite compound represented by the formula: R-M-X.sub.3, R representing an organic molecule, M representing a metal atom, X representing a halogen atom or a chalcogen atom, the encapsulation resin layer including a resin having a solubility parameter, i.e., a SP value, of 10 or less.

A method of growing a III-V semiconductor compound film for a semiconductor device including the steps of depositing a textured oxide buffer layer on an inexpensive substrate, depositing a metal-inorganic film from a eutectic alloy on the buffer layer, the metal being a component of a III-V compound and forming a layer on the inorganic film on which additional elements from the III-V compound are added, forming a top layer of a tandem solar cell.