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Halide perovskite light-emitting electrochemical cells are a novel type of the perovskite optoelectronic devices that differs from the perovskite light-emitting diodes by a simple monolayered architecture. Here, we develop a perovskite electrochemical cell both for light emission and detection, where the active layer consists of a composite material made of halide perovskite microcrystals, polymer support matrix, and added mobile ions. The perovskite electrochemical cell of CsPbBr3:PEO:LiTFSI composition, emitting light at the wavelength of 523 nm, yields the luminance more than 7000 cd/m2 and electroluminescence efficiency of 1.3×105 lm/W. The device fabricated on a silicon substrate with transparent single-walled carbon nanotube film as a top contact exhibits 40% lower Joule heating compared to the perovskite optoelectronic devices fabricated on conventional ITO/glass substrates. Moreover, the device operates as a photodetector with a sensitivity up to 0.75 A/W, specific detectivity of 8.56×1011 Jones, and linear dynamic range of 48 dB. The technological potential of such a device is proven by demonstration of 24-pixel indicator display as well as by successful device miniaturization by creation of electroluminescent images with the smallest features less than 50 μm.

Abstract Electric field is a powerful instrument in nanoscale engineering, providing wide functionalities for control in various optical and solid-state nanodevices. The development of a single optically resonant nanostructure operating with a charge-induced electrical field is challenging, but it could be extremely useful for novel nanophotonic horizons. Here, we show a resonant metal-semiconductor nanostructure with a static electric field created at the interface between its components by charge carriers generated via femtosecond laser irradiation. We study this field experimentally, probing it by second-harmonic generation signal, which, in our system, is time-dependent and has a non-quadratic signal/excitation power dependence. The developed numerical models reveal the influence of the optically induced static electric field on the second harmonic generation signal. We also show how metal work function and silicon surface defect density for different charge carrier concentrations affect the formation of this field. We estimate the value of optically-generated static electric field in this nanoantenna to achieve ≈108V/m. These findings pave the way for the creation of nanoantenna-based optical memory, programmable logic and neuromorphic devices.

Abstract Surfaces with special wettability properties, such as omniphobicity or omniphilicity, are essential for functional devices that use both aqueous and organic media. Micropatterning of omniphobic and omniphilic properties can provide a wide range of applications, including miniaturized experiments using both aqueous and organic media. Herein, an approach for creating omniphobic‐omniphilic micropatterns based on selective photoacid polymerization of octa(3‐glycidyloxypropyl) polyhedral oligomeric silsesquioxane modified with mono‐aminopropyl‐terminated polydimethylsiloxane is reported. The composition of the polymeric coatings using infrared spectroscopy; patterning accuracy using atomic force microscopy and scanning electron microscopy; wettability characteristics of the omniphobic, and omniphilic surfaces using contact angle measurements are studied. The proposed approach allows for single‐step micropatterning (sub‐10 µm) or macropatterning (3 mm). Liquids with surface tensions >22.8 mN m−1 can be confined to the omniphilic areas by the omniphobic borders. C2C12 cells are successfully cultivated in omniphilic areas, demonstrating their cell compatibility. The cells adhere to and grow on the entire surface of the pattern, without any signs of cytotoxicity. However, the strongest adhesion is observed in the omniphilic areas, making it possible to create cell micropatterns in a single step. The proposed method for the fabrication of omniphobic‐omniphilic transparent, mechanically robust, biocompatible patterns can find applications in microfluidics, biotechnology or miniaturized biological screening experiments.

We report on half-ring lasers that are 100–200 µm in diameter and are fabricated by cleaving the initial full rings into halves. Characteristics of the half-ring and half-disk lasers fabricated from the same wafer are compared. The active area of the microlasers is based on the quantum heterostructures of mixed (0D/2D) dimensionality, referred to as quantum well-dots with very high material gain. Half-ring lasers show directional light emission and single-mode lasing near the threshold. A maximal continuous-wave output power of 76 mW is achieved for a half-ring that is 200 µm in diameter. Half-rings demonstrate better wall-plug efficiency as compared to half-disks. Lasing in pulse mode is observed up to 140 °C, the characteristic temperature is 100–125 K, depending on the half-ring size. P-side down bonding onto Si-board significantly improves power and temperature characteristics. In CW mode, lasing is maintained up to 97 °C, limited by active-area overheating.

The direct integration of epitaxial III-V and III-N heterostructures on Si substrates is a promising platform for the development of optoelectronic devices. Nanowires, due to their unique geometry, allow for the direct synthesis of semiconductor light-emitting diodes (LED) on crystalline lattice-mismatched Si wafers. Here, we present molecular beam epitaxy of regular arrays n-GaN/i-InGaN/p-GaN heterostructured nanowires and tripods on Si/SiO2 substrates prepatterned with the use of cost-effective and rapid microsphere optical lithography. This approach provides the selective-area synthesis of the ordered nanowire arrays on large-area Si substrates. We experimentally show that the n-GaN NWs/n-Si interface demonstrates rectifying behavior and the fabricated n-GaN/i-InGaN/p-GaN NWs-based LEDs have electroluminescence in the broad spectral range, with a maximum near 500 nm, which can be employed for multicolor or white light screen development.

It is shown for the first time that the vacuum poling of soda-lime silicate glass and the subsequent processing of the glass in a melt containing silver ions results in the formation of silver nanoparticles buried in the subanodic region of the glass at a depth of 800–1700 nm. We associate the formation of nanoparticles with the transfer of electrons from negatively charged non-bridging oxygen atoms to silver ions, their reduction as well as their clustering. The nanoparticles do not form in the ion-depleted area just beneath the glass surface, which indicates the absence of a spatial charge (negatively charged oxygen atoms) in this region of the vacuum-poled glass. In consequence, the neutralization of the glass via switching of non-bridging oxygen bonds to bridging ones, which leads to the release of oxygen, should occur in parallel with the shift of calcium, magnesium, and sodium ions into the depth of the glass.

We demonstrate flexible red light-emitting diodes based on axial GaPAs/GaP heterostructured nanowires embedded in polydimethylsiloxane membranes with transparent electrodes involving single-walled carbon nanotubes. The GaPAs/GaP axial nanowire arrays were grown by molecular beam epitaxy, encapsulated into a polydimethylsiloxane film, and then released from the growth substrate. The fabricated free-standing membrane of light-emitting diodes with contacts of single-walled carbon nanotube films has the main electroluminescence line at 670 nm. Membrane-based light-emitting diodes (LEDs) were compared with GaPAs/GaP NW array LED devices processed directly on Si growth substrate revealing similar electroluminescence properties. Demonstrated membrane-based red LEDs are opening an avenue for flexible full color inorganic devices.