Combining the advantages of low-dimensional and wide-gap semiconductors, InGaN quantum dots (QDs) are widely investigated as a candidate material for high-efficiency micro-LEDs. In this work, plasma-assisted molecular beam epitaxy (PAMBE) was used to grow self-assembled InGaN QDs for the fabrication of green micro-LEDs. The InGaN QDs have a rather high density of over 3.0×1010 cm−2 and show good dispersion and relatively uniform size distribution. A green LED with the size of 300 μm × 300 μm based on InGaN/GaN multi-quantum dots (MQDs) was fabricated. In addition, the preparation of micro-LEDs with different diameters (from 4 μm to 20 μm) and arrays of them with an emission wavelength of 537 nm have been finished. The luminescence tests show that InGaN QD-based micro-LEDs have excellent wavelength stability with the increase of injection current density, which is attributed to the shielding effect of QDs on the polarized field. This performance is of great significance for full-color micro-LED displays.
Biosensors based on carbon nanotube (CNT) thin-film transistors (TFTs) have outstanding potential for ultrasensitive and label-free DNA detection. However, at present, the sensing mechanisms of the all-carbon-nanotube biosensors with metallic CNTs as electrodes are still controversial. In this work, a platform is established for universal DNA detection. By analyzing the biosensor responses obtained by passivating the channel, electrodes and contact of the biosensors, respectively, the sensing mechanisms can be clearly investigated. It is found that the electrostatic gating is dominant, while the Schottky barrier modulation plays a relatively minor role, where the Schottky barrier height is co-modulated by the adsorbed DNA in the channel and electrodes.
Nanophotonic multispectral absorbers and their enhanced optoelectronic performance have been studied in the research areas of photonics. The graphene-based quasi-photonic structures has amended the progress in this area. In this paper, the temperature tunable absorption was explored numerically using the proposed graphene-based phase change material (PCM) nanocomposite cavity in the photonic structure. This work observes higher multiband absorption in the infrared spectrum with thermal tuning and resonant frequency switchable with variation of composite material. The design procedure of cavities improves higher quality factor (Q) and Full-Width Half-Maximum (FWHM) compared to other literature with the inclusion of graphene as a defect. The temperature-dependent graphene-based nanocomposite cavity in the proposed structure varies absorption peaks with changes in defect layer thickness, chemical potential of the graphene layer, and angle of the incident light. The performance of the structure was also studied in terms of absorption behavior under oblique incidence, enhanced Q-factor and FWDM with blue shift resonant frequency under different polarizations are observed. These observations can be used for designing optical filters and narrowband optical absorbers.
Feedback-controlled electromigration method has been known to fabricate the atomic junction by controlling the quantized conductance on the Au nanowires. We demonstrated a real-time prediction of the quantized conductance on the Au nanowires dynamically inferred by reservoir computing on a real-time operating system. As a result, the root mean squared error in ballistic regime of the proposed system is 0.414. We believe that our system makes a valuable contribution to the fabrication of nanoscale devices in that it introduces the real-time prediction under running processes.
While there have been extensive reports in literature regarding the synthesis of porous silicon layers using electrochemical anodization for their use in different applications, systematic studies regarding the influence of the substrate dopant concentration and the electrolyte composition on the pore dimensions have not not been extensively investigated. In this work, we have systematically looked at the influence of dopant concentration and different electrolyte compositions on the pore dimensions of the porous silicon layer, along with varying input current density and reaction time.
