The behavior of an illuminated solar module can be characterized by its power-voltage curve. Tracking the peak of this curve is essential to harvest the maximum power by the module. The position of the peak varies with temperature and irradiance and needs to be traced.
View Article and Find Full Text PDFIn the rapidly developing area of magnetoionics (MI), which combines electrochemistry and magnetism, changes in the surface chemistry of magnetic materials in response to gate voltages cause dramatic modifications in the magnetic characteristics, resulting in low power-consuming charge transport tuning. Due to the surficial character, only magnetic thin films have been addressed for the MI effect's role in controlling charge transfer. Here, we show how it can be used to regulate the transit of charges in bulk magnetic materials.
View Article and Find Full Text PDFACS Appl Mater Interfaces
October 2023
The challenging environmental chemical and microbial pollution has always caused issues for human life. This article investigates the detailed mechanism of photodegradation and antimicrobial activity of oxide semiconductors and realizes the interface phenomena of nanostructures with toxins and bacteria. We demonstrate how oxygen vacancies in nanostructures affect photodegradation and antimicrobial behavior.
View Article and Find Full Text PDFDelafossite semiconductors have attracted substantial attention in the field of electro-optics owing to their unique properties and availability of p-type materials that are applicable for solar cells, photocatalysts, photodetectors (PDs) and p-type transparent conductive oxides (TCOs). The CuGaO (CGO), as one of the most promising p-type delafossite materials, has appealing electrical and optical properties. In this work, we are able to synthesize CGO with different phases by adopting solid-state reaction route using sputtering followed by heat treatment at different temperatures.
View Article and Find Full Text PDFWe investigate the realization of the phenomenon of optomechanically induced gain in a hybrid optomechanical system consisting of an interacting Bose-Einstein condensate trapped inside the optical lattice of a cavity which is generated by an external coupling laser tuned to the red sideband of the cavity. It is shown that the system behaves as an optical transistor while the cavity is exposed to a weak input optical signal which can be amplified considerably in the cavity output if the system is in the unresolved sideband regime. Interestingly, the system has the capability to switch from the resolved to unresolved sideband regime by controlling the s-wave scattering frequency of atomic collisions.
View Article and Find Full Text PDFIn this article, we propose an experimentally feasible scheme for the ultraslow light realization based on the optomechanically induced transparency (OMIT) phenomenon using a hybrid optomechanical system consisting of a one-dimensional Bose-Einstein condensate trapped in a shallow optical lattice considering the nonlinear effect of atom-atom interaction. It is shown how the system can switch from the normal mode splitting to the OMIT regime by manipulation of the s-wave scattering frequency of atomic collisions when the cavity is pumped at a fixed rate. Then, it is shown that an ultraslow light with a time delay more than 150 ms corresponding to a group velocity about 1 mm/s is achievable by controlling the optical lattice depth as well as the strength of atom-atom interaction and the number of atoms.
View Article and Find Full Text PDFMetamaterial photonic integrated circuits with arrays of hybrid graphene-superconductor coupled split-ring resonators (SRR) capable of modulating and slowing down terahertz (THz) light are introduced and proposed. The hybrid device's optical responses, such as electromagnetic-induced transparency (EIT) and group delay, can be modulated in several ways. First, it is modulated electrically by changing the conductivity and carrier concentrations in graphene.
View Article and Find Full Text PDFWe propose and fabricate a heterojunction between Al-doped ZnO and (Mg, N)-doped CuCrO thin films using the sputtering deposition method. These materials possess wide bandgap that makes them transparent in the visible light but excellent UV-absorbers. On the other hand, the high conductivity of these materials, respectively as n-type and p-type transparent conducting oxides, facilitates the charge transport.
View Article and Find Full Text PDFA novel method of oxide semiconductor nanoparticle synthesis is proposed based on high-voltage, high-current electrical switching discharge (HVHC-ESD). Through a subsecond discharge in the HVHC-ESD method, we successfully synthesized zinc oxide (ZnO) nanorods. Crystallography and optical and electrical analyses approve the high crystal-quality and outstanding optoelectronic characteristics of our synthesized ZnO.
View Article and Find Full Text PDFPlasmonics, as a rapidly growing research field, provides new pathways to guide and modulate highly confined light in the microwave-to-optical range of frequencies. We demonstrated a plasmonic slot waveguide, at the nanometer scale, based on the high-transition-temperature () superconductor BiSrCaCuO (BSCCO), to facilitate the manifestation of chip-scale millimeter wave (mm-wave)-to-terahertz (THz) integrated circuitry operating at cryogenic temperatures. We investigated the effect of geometrical parameters on the modal characteristics of the BSCCO plasmonic slot waveguide between 100 and 800 GHz.
View Article and Find Full Text PDFFor the first time, a hard wear-resistant multi-layer of TiCrN-TiAlN-TiAlSiN-TiAlSiCN was deposited on carbon steel CK45-based tillage tools to increase their useful lifetime. The layers were deposited by using an arc-PVD method without post-annealing procedures. XRD and EDX data indicated that TiCrN, TiAlN, TiAlSiN, and TiAlSiCN formed individually and as a multi-layer of high-quality crystalline layers with mostly cubic structures.
View Article and Find Full Text PDFA fiber optic-based all-optical amplifier is designed by using the coherent perfect absorption phenomenon. For this purpose, we use a deposited chromium thin layer as an absorbent material on the cross-section of a PM fiber. By placing another fiber in front of the deposited one, we show that by controlling the relative phase between the two counter-propagating beams, total absorbance can be controlled.
View Article and Find Full Text PDFThis study aims to design an all-optical transistor based on tunneling of light through frustrated total internal reflection. Under total internal reflection, the electromagnetic wave penetrates into the lower index medium. If a medium with high refractive index is placed close to the boundary of the first one, a portion of light leaks into the second medium.
View Article and Find Full Text PDFIn order to construct flat-top magneto-optical isolators (MOIs), we have performed a theoretical study on the case of transmission-type one-dimensional magnetophotonic crystals (MPCs). We have introduced high performance MPC structures with flat-top responses and with the capability of adjusting to perfect MOIs. The adjustment is carried out by tuning the applied magnetic field.
View Article and Find Full Text PDFIn this article, we introduce a simple magnetophotonic crystal structure for magnetic field sensing applications. Design procedure, which is performed using a global optimization tool called genetic algorithm, provides great flexibility for structures with layers having nonquarter-wavelength thickness. Results show that our proposed genetic sensor comparatively exhibits higher simplicity, sensitivity, and spatial resolution, with better photo-response and performance.
View Article and Find Full Text PDFWe have performed a theoretical study on the case of transmission-type one-dimensional magnetophotonic crystals (MPCs) to establish a practical magneto-optical isolator (MOI) that operates properly even in the presence of construction errors. We have introduced a very thin MPC structure with high transmittance and a large Faraday rotation, with the capability of adjusting to a perfect MOI. A minor thickness error for the individual layers of this MOI may take it from being a perfect MOI; however, its adjustability can provide a stable operation against fabrication errors.
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