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Non‐peripherally, glycerol terminal groups substituted copper (II) phthalocyanine were non‐covalently (electrostatic and/or π–π interaction) attached to carbon (CQD) and carbon‐boron quantum dots (CBQD) to form QDs‐Pc nanoconjugate systems. Synthesized novel phthalocyanine compounds and QDs‐Pc conjugate systems were characterized using different spectroscopic techniques. Various biological assessments were applied to newly synthesized compounds. Conjugates 4 and 5 had a maximal free radical scavenging activity of 71.3% and 68.1% at a 100 mg/L concentration. Compounds exhibited high antidiabetic activities at 200 mg/L. Also, compounds showed significant DNA nuclease activity at all tested concentrations. The most efficient MIC value was obtained as 4 mg/L against Enterococcus hirae and Enterococcus feacalis. This MIC value was further decreased after photodynamic therapy, and it was observed that the antimicrobial effects of the compounds increased. Inhibition of microbial cell viability was obtained as 100% for all compounds. In addition, compounds exerted perfect biofilm inhibitory effects. [ABSTRACT FROM AUTHOR]

Despite the promising applications of the use of quantum dots (QDs) in the biomedical field, the long-lasting effects of QDs on the cell remain poorly understood. To comprehend the mechanisms underlying the toxic effects of QDs in yeast, we characterized defects associated with receptor-mediated endocytosis (RME) as well as pinocytosis using Saccharomyces cerevisiae as a model in the presence of cadmium selenide/zinc sulfide (CdSe/ZnS) QDs. Our findings revealed that QDs led to an inefficient RME at the early, intermediate, and late stages of endocytic patch maturation at the endocytic site, with the prolonged lifespan of GFP fused yeast fimbrin (Sac6-GFP), a late marker of endocytosis. The transit of FM1-43, a lipophilic dye from the plasma membrane to the vacuole, was severely retarded in the presence of QDs. Finally, QDs caused an accumulation of monomeric red fluorescent protein fused carbamoyl phosphate synthetase 1 (mRFP-Cps1), a vacuolar lumen marker in the vacuole. In summary, the present study provides novel insights into the possible impact of CdSe/ZnS QDs on the endocytic machinery, enabling a deeper comprehension of QD toxicity. [ABSTRACT FROM AUTHOR]

In this work, the impact of Ag–In–S quantum dots (QDs) on the dielectric and electro-optical characteristics of E7 nematic liquid crystal (NLC) is investigated. To realize the objective, various concentrations of Ag–In–S QDs (0.2, 0.4, 0.6, 0.8, and 1 wt%) were added to E7 NLC, and the resulting composites were then introduced into homogeneous, homeotropic, and twisted nematic aligned cells. The temperature dependence property of the parallel and perpendicular components of the dielectric constant (ɛ∥ & ε ⊥ ) for pure and QDs-doped NLCs was measured. ɛ∥ significantly enhanced in the presence of 0.8 wt% of the QDs, which led to a ~ 23% rise in the dielectric anisotropy of the system. The dielectric results demonstrated that NLC hosts prompt QDs to form self-assembled arrays within the NLC system. In addition, electro-optical measurements revealed the considerable impact of QDs doping on the reduction of threshold voltage (Vth). Importantly, a ~ 15% decrease in Vth was observed for NLC doped with 0.8 wt% of the QDs compared to pure NLC. Besides, the addition of QDs significantly accelerates the NLC electro-optical response. The switch-on and -off response times for the QDs-doped NLC cell were reduced by ~ 34% and ~ 41%, respectively, compared to those for the pure NLC cell. A combination of increased dielectric anisotropy, improved mutual interactions of components, and reduced rotational viscosity of the mixture may result in much faster electro-optical switching responses. The presented achievements in this study will be beneficial in the development of LC-based display panels as well as switchable smart windows. [ABSTRACT FROM AUTHOR]

In this work, a highly efficient photosensitive quantum dot (QD) system was designed. The optimized photosensitive QD system had high photoluminescence quantum yield and colloidal stability. By direct photolithography, RGB pixel arrays with a single sub‐pixel size of 39 μm × 5 μm were successfully prepared. Further, the full‐color QLED device was realized. There were no residual QD emission peaks from neighboring sub‐pixels observed in the electroluminescence spectra. Experience on the full‐color QLED device guided the successful preparation of a 4.7‐inch 650 PPI active matrix QLED prototype. The active matrix QLED prototype could display clear and complete pictures. The color gamut reached 85% of the BT2020 standard. This is the first active matrix QLED prototype prepared with a record‐high resolution by direct photolithography, which promoted the development of QLED display technology. [ABSTRACT FROM AUTHOR]

We constructed ZnO quantum dots (QDs) with a diameter of 1.2 nm of wurtzite structure, hydrogenated the surface and doped single Mn atoms using Zn-site substitution. We present an investigation of the structural and electronic properties of ZnO QDs of three doping sites: inner, intermediate and outer. Based on the density functional theory and the plane-wave pseudo potential method, the structural characteristics, charge distribution, conductivity and formation energy of doped ZnO QDs are analyzed. We obtained the effect of doping site depth on the properties above with the nearly optimal nanoparticle doping concentration (2.222%). The internal doping (inner and intermedium) configuration results in higher electrical conductivity and stronger bonds than the outer doping configuration. In particular, intermediate doping is highly efficient and valuable for obtaining Mn-doped ZnO nanoparticles with good structural and electronic properties. This study provides a theoretical reference for the survey of zero-dimensional dilute magnetic semiconductors. [ABSTRACT FROM AUTHOR]

The technology of RGBY micro resonant cavity light emitting diodes (micro-RCLEDs) based on quantum dots (QDs) is considered one of the most promising approaches for full-color displays. In this work, we propose a novel structure combining a high color conversion efficiency (CCE) QD photoresist (QDPR) color conversion layer (CCL) with blue light micro RCLEDs, incorporating an ultra-thin yellow color filter. The additional TiO2 particles inside the QDPR CCL can scatter light and disperse QDs, thus reducing the self-aggregation phenomenon and enhancing the eventual illumination uniformity. Considering the blue light leakage, the influences of adding different color filters are investigated by illumination design software. Finally, the introduction of low-temperature atomic layer deposition (ALD) passivation protection technology at the top of the CCL can enhance the device's reliability. The introduction of RGBY four-color subpixels provides a viable path for developing low-energy consumption, high uniformity, and efficient color conversion displays. [ABSTRACT FROM AUTHOR]

Quantum dot light-emitting diodes (QLEDs) are increasingly being recognized as next-generation display technology, owing to their wide color gamut, high saturation levels, and low energy consumption. However, the primary challenge in QLED display fabrication lies in precisely depositing these inorganic quantum dot (QD) nanoparticles over a large area multiple times. Nowadays, solution processes such as inkjet printing and screen printing have been employed to address these challenges; however, they still have some trade-offs between multicolor deposition, precise spatial arrangement, and equipment cost. Here, the precise assembly of multiple QD patterned arrays on one target substrate was achieved using an asymmetric wettability interface assembly (AWIA) template, resulting in a high-pixel resolution and full-color QLED device. The asymmetric wettability interface between the top and bottom of the silicon pillar on the template allows for precise splitting and pinning of a continuous liquid film, facilitating further assembly of QD pattern arrays. Additionally, the multicolor and multishape QD pattern array was created through QD surface modification (orthogonal solvent protection) and dislocation pinning processes (reducing dissolution time) during the repetition process. Consequently, high-resolution (each pixel ≈ 10 μm; PPI ≈ 1278) full-color (yellow, cyan, violet, and white) QLED devices were fabricated efficiently. This approach offers a perspective for assembling multiple micropatterned arrays for high-resolution electronic devices. [ABSTRACT FROM AUTHOR]

Due to the inherent high dark current of photoelectrochemical (PEC)‐type photodetectors (PDs), there is a tricky challenge to detect weak light. In this work, high‐quality Cd0.9Pb0.1Se quantum dots (CPS QDs) are prepared by thermal injection method, with horizontal size of 6.3 nm and thickness of 3.5 nm. The CPS QDs are directly utilized to construct the working electrode of PEC‐type PDs. The effects of experimental parameters on the photo‐response behavior are systematically studied, and optimized photocurrent density of 7.1 µA cm−2 and photo‐responsivity (Rph) of 2.75 mA·W−1 are achieved. Most importantly, the obvious photocurrent signals are observed under a light power density as low as 5.6 µW cm−2. For this interesting weak light detection, apparent Rph of 6.96 mA·W−1, detectivity of 1.2 × 109 Jones, and external quantum efficiency of 2.37% are achieved. Therefore, this work not only develops CPS QDs‐based PDs but also provides an example for PEC‐type PDs in weak light detection. [ABSTRACT FROM AUTHOR]

Gaining insight into nanostructure devices represents a crucial step in unlocking their full quantum potential. Solid-state quantum dots provide a practical and scalable foundation for accommodating qubits, which are essential for quantum information processing. In this context, we introduce a model involving a pair of qubits within a double quantum dot configuration. We extensively investigate its quantum coherence and the quantum-memory-assisted entropic uncertainty relation ( QMA - EUR ), considering the influence of the thermal environment and Rashba spin–orbit coupling. Our findings reveal a monotonic increase in QMA - EUR with rising temperatures (T), while the Jensen–Shannon coherence consistently decreases as T increases. Furthermore, fine-tuning the Rashba coupling can enhance the system's coherence and reduce measurement uncertainty. We show that obtaining higher measurement precisions is achievable when the two-qubit system, made up of the double quantum dots with Rashba interaction, demonstrates higher levels of coherence. Additionally, we demonstrate that adjusting other Hamiltonian parameters offers advantages in preserving quantum resources. These reported results indicate promising prospects for developing quantum technologies that leverage such a quantum dot system. [ABSTRACT FROM AUTHOR]

Entanglement purification is an important and useful tool in quantum communications that allows parties to enhance the entanglement of a set of less-entangled particles using local operations and classical communication. Utilizing photon polarization parity checks implemented through the coupling system between a single-sided cavity and a charged quantum dot, an entanglement purification scheme is proposed in this paper. The fidelity and the success probability of the scheme are calculated under bit-flip error channel and depolarizing channel, respectively. Furthermore, the impact of imperfect quantum-dot-cavity coupling system is investigated, and the feasibility is discussed. In the strong coupling and weak cavity side leakage regime, our scheme can approach the maximal fidelities and success probabilities in theory. So the scheme has potential applications in long-distance quantum communication with the development of relevant technologies. [ABSTRACT FROM AUTHOR]

In the paper, the electronic properties of a quantum dot (QD) using the Frost–Musulin potential model are investigated taking into account both an external magnetic field and electron–electron interaction. For this purpose, the Schrödinger equation (SE) is analytically solved without considering electron–electron interaction by employing the Nikiforov–Uvarov (NU) procedure, and the energy levels and wave functions are determined. Then, the singlet–triplet (ST) transition is studied for different values of magnetic fields. According to our results, Both the dot size and magnetic field have key roles in the ground state transition. The ST transition of the ground state moves to lower magnetic fields as the QD size is increased. However the transition occurs at higher magnetic fields when the potential depth is increased. The transition for small QD size occurs only from 1S to 3P. But by increasing the QD size, another transition is also observed from 1D to 3F. These transitions occur at smaller magnetic fields when the QD size is increased. [ABSTRACT FROM AUTHOR]

Quantum dot light‐emitting diodes (QLEDs) is one of the most important components in the display field, and different structures have a certain impact on the final performance of the device. Previous QLEDs mainly use ZnO nanocrystals as the electron transport layer (ETL), but the chemical activity of ZnO nanocrystals under electric fields and moisture is not stable enough. To solve this problem, this paper studies the effects of TiO2 films with different thicknesses on the luminescence, current density and external quantum efficiency of QLED devices by using magnetron sputtered TiO2 as a new ETL. The experimental results show that the 50nm TiO2 film achieves the highest external quantum efficiency while maintaining favorable current density and brightness. [ABSTRACT FROM AUTHOR]

Numerous optoelectronic devices based on low-dimensional nanostructures have been developed in recent years. Among these, pyramidal low-dimensional semiconductors (zero- and one-dimensional nanomaterials) have been favored in the field of optoelectronics. In this review, we discuss in detail the structures, preparation methods, band structures, electronic properties, and optoelectronic applications (photocatalysis, photoelectric detection, solar cells, light-emitting diodes, lasers, and optical quantum information processing) of pyramidal low-dimensional semiconductors and demonstrate their excellent photoelectric performances. More specifically, pyramidal semiconductor quantum dots (PSQDs) possess higher mobilities and longer lifetimes, which would be more suitable for photovoltaic devices requiring fast carrier transport. In addition, the linear polarization direction of exciton emission is easily controlled via the direction of magnetic field in PSQDs with C3v symmetry, so that all-optical multi-qubit gates based on electron spin as a quantum bit could be realized. Therefore, the use of PSQDs (e.g., InAs, GaN, InGaAs, and InGaN) as effective candidates for constructing optical quantum devices is examined due to the growing interest in optical quantum information processing. Pyramidal semiconductor nanorods (PSNRs) and pyramidal semiconductor nanowires (PSNWRs) also exhibit the more efficient separation of electron-hole pairs and strong light absorption effects, which are expected to be widely utilized in light-receiving devices. Finally, this review concludes with a summary of the current problems and suggestions for potential future research directions in the context of pyramidal low-dimensional semiconductors. [ABSTRACT FROM AUTHOR]

Present enquiry thoroughly explores the time-average excitation rate (TAER) of GaAs quantum dot (QD) pursuing the change in the anharmonicity binding energy (ABE) of the system and under the supervision of Gaussian white noise (GWN). The promotion of the ground state electronic density occurs due to various kinds of time-varying fluctuations viz. simple sinusoidal field (SSF), time-dependent confinement potential (TDCP), time-dependent magnetic field (TDMF), polychromatic radiation field (PRF), pulsed field (PF), chirped pulsed field (CPF), time-dependent anharmonicity constant (TDAC) and time-dependent noise strength (TDNS). GWN couples with the QD by additive and multiplicative modes. The work analyzes the consequence of joint influence of a few parameters that guides the attributes of the TAER diagrams. These parameters involve ABE, inclusion of GWN in a given pathway, the parity of the anharmonic potential and the type of the time-dependent perturbations. The TAER curves are enriched with steadfast rise, steadfast diminish, maximization (relevant to generation of large nonlinear optical properties), minimization and saturation (suggesting dynamic freezing). The findings highlight the utility of different kinds of time-dependent fluctuations to fine-tune the TAER among the GaAs QD eigenfunctions when the ABE of QD carries out a continual change. [ABSTRACT FROM AUTHOR]

A quantum dot (QD) is a semiconducting nanocrystal with exceptional luminescence emissions. Their semiconductor characteristics differ from those of bulk materials due to quantum confinement. Due to these characteristics, QDs can be used as a luminous probe for biological and pharmacological investigations. The purpose of this section is to examine the creation, modification, characterization and application of QDs. Due to their potential for imaging and targeting applications in drug delivery, quantum dots have attracted the attention of scientists. In the current work, we have thoroughly evaluated a variety of QD-related topics, emphasizing their pharmacology, interactions, pharmacological and biological uses and toxicological manifestations. The goal of QD usage is to significantly enhance clinical diagnostic procedures for early cancer detection. QDs are a new fluorescent probe that has been introduced to cell biology in recent years. This review's objective is to list and examine the benefits and drawbacks of QDs and the applications for which they are used. [ABSTRACT FROM AUTHOR]

The discrimination and recognition of biological targets, such as proteins, cells, and bacteria, are of utmost importance in various fields of biological research and production. These include areas like biological medicine, clinical diagnosis, and microbiology analysis. In order to efficiently and cost-effectively identify a specific target from a wide range of possibilities, researchers have developed a technique called differential sensing. Unlike traditional "lock-and-key" sensors that rely on specific interactions between receptors and analytes, differential sensing makes use of cross-reactive receptors. These sensors offer less specificity but can cross-react with a wide range of analytes to produce a large amount of data. Many pattern recognition strategies have been developed and have shown promising results in identifying complex analytes. To create advanced sensor arrays for higher analysis efficiency and larger recognizing range, various nanomaterials have been utilized as sensing probes. These nanomaterials possess distinct molecular affinities, optical/electrical properties, and biological compatibility, and are conveniently functionalized. In this review, our focus is on recently reported optical sensor arrays that utilize nanomaterials to discriminate bioanalytes, including proteins, cells, and bacteria. [ABSTRACT FROM AUTHOR]

Semiconductor photocatalysis has recently emerged as a promising method for microbial inactivation. So far, quantum dots have generally been investigated as antibacterial suspension. Instead, here we demonstrate a InP/ZnS quantum dot nanoassembly film against both Gram-negative and Gram-positive bacteria. For effective operation in the solid phase, a thin layer of ZnS shell was grown on InP QD and the native long-chain ligand of stearic acid was replaced with sulfide that led to a high quantum yield of superoxide generation as 4.9%. QDs are assembled onto solid surfaces through sequential dip coating of positively charged poly-(diallyldimethylammonium chloride) and negatively charged QDs. These QD nanoassemblies demonstrate growth inhibition against Escherichia coli and multidrug-resistant Staphylococcus aureus under illumination. Interestingly, such an approach can be directly applied to irregular surfaces, as well. This study unveils the potential of the nanoengineering of QDs for antibacterial coatings. [ABSTRACT FROM AUTHOR]

The hot injection method is a commonly employed technique for the synthesis of perovskite nanoparticles that are subsequently used in the fabrication of perovskite solar cells (PSCs). However, this method presents a significant challenge related to the removal of ligands and the purification of nanoparticles. The issue arises from the use of long-chain ligands that are crucial for stabilizing the nanoparticles during their synthesis. These long-chain ligands, while serving their purpose during nanoparticle formation, can pose hindrances when the nanoparticles are integrated into a solar cell. Here, we prepared CsPbIBr2 nanoparticles stabilized with a short-chain ligand, amylamine (C5H13N). These nanoparticles were used to create nanoparticle films without the need for additional cleaning and purification steps. Subsequently, a high-quality bulk film was obtained by heat treatment. Additionally, we introduced a fast dual-step centrifugal deposition method differing from the conventional layer-to-layer spin coating approach. Films produced using this dual-step centrifugal deposition method exhibited a grain size of approximately 220 nm and near-vertical growth. As a result, our perovskite solar cells achieved a superior power conversion efficiency (PCE) exceeding 7.1%. This simplified and expeditious fabrication method holds promising implications for streamlining the perovskite solar cell production process in the future. [ABSTRACT FROM AUTHOR]

A spectral model is constructed for the luminescence of a two-component exciton-activated quantum dot (QD)–spheroidal plasmon nanoparticle (NP) system in a homogeneous external magnetic field in the approximation of a dipole electric polarizability tensor of the nanoparticle with dissipation of the exciton energy in the NP taken into account. A tensor representation of the dielectric permeability of the magnetized electron plasma of the metal is used, which is responsible for the formation of the characteristics of the electric field in the spheroid. It is found that with a change in the eccentricity of the spheroid, the luminescence spectrum of the system changes, reflecting the effect of the external magnetic field on both the radiative and the dissipative properties of the binary QD–NP complex. [ABSTRACT FROM AUTHOR]

The cell nucleus is the main site for the storage and replication of genetic material, and the synthesis of substances in the nucleus is rhythmic, regular and strictly regulated by physiological processes. However, whether exogenous substances, such as nanoparticles, can be synthesized in situ in the nucleus of live cells has not been reported. Here, we have achieved in-situ synthesis of CdS x Se1−x quantum dots (QDs) in the nucleus by regulation of the glutathione (GSH) metabolic pathway. High enrichment of GSH in the nucleus can be accomplished by the addition of GSH with the help of the Bcl-2 protein. Then, high-valence Se is reduced to low-valence Se by glutathione-reductase-catalyzed GSH, and interacts with the Cd precursor formed through Cd and thiol-rich proteins, eventually generating QDs in the nucleus. Our work contributes to a new understanding of the syntheses of substances in the cell nucleus and will pave the way for the development of advanced 'supercells'. [ABSTRACT FROM AUTHOR]

Graphene quantum dots (GQDs) possess the photosensitive absorption for photoelectrochemical hydrogen evolution owing to special band structures, whereas they usually confront with photo-corrosion or undesired charge recombination during photoelectrochemical reactions. Hence, we establish the heterojunction between GQDs and MoSe2 sheets via a hydrothermal process for improved stability and performance. Photoanodic water splitting with hydrogen evolution boosted by the heteroatom doped N,S-GQDs/MoSe2 heterojunction has been attained due to the abundant active sites, promoted charge separation and transfer kinetics with reduced energy barriers. Diphasic 1T and 2H MoSe2 sheet-hybridized quantum dots contribute to the Schottky heterojunction, which can play a key role in expedited carrier transport to inhibit accumulative photo-corrosion and increase photocurrent. Heteroatom dopants lead to favored energy band matching, bandgap narrowing, stronger light absorption and high photocurrent density. The external quantum efficiency of the doped heterojunction has been elevated twofold over that of the non-doped pristine heterojunction. Modification of the graphene quantum dots and MoSe2 heterojunction demonstrate a viable and adaptable platform toward photoelectrochemical hydrogen evolution processes. [ABSTRACT FROM AUTHOR]

This paper explores the role of spatial extension of impurity (SEI) on two nonlinear optical (NLO) properties and two other related properties of impurity doped GaAs quantum dot (QD). The NLO properties include the electro-optic effect (EOE) and the third-order nonlinear optical susceptibility (TONOS) whereas the other two related properties being total optical dielectric function (TODF) and the intraband transition lifetime (ITL). The study also involves Gaussian white noise (GWN) which has been introduced to the doped QD through additive and multiplicative pathways. The investigation unveils the subtle interplay between GWN and SEI which ultimately fine-tunes the said NLO properties. TODF, EOE and TONOS manifest red-shift with enhancement of SEI both with and without GWN. The ITL, on the other hand, exhibits monotonic growth with increase in SEI under all conditions. Moreover, the application of GWN causes noticeable quenching of the NLO properties. And the quenching becomes more stringent in presence of multiplicative noise than its additive counterpart. [ABSTRACT FROM AUTHOR]

We theoretically investigate the Seebeck and Peltier effect across an interacting quantum dot (QD) coupled between a normal metal and a Bardeen–Cooper–Schrieffer superconductor within the Coulomb blockade regime. Our results demonstrate that the thermoelectric conversion efficiency at optimal power output (optimized with respect to QD energy level and external serial load) in NQDS nanodevice can reach up to 58 % η C , where η C is Carnot efficiency, with output power P max ≈ 35 fW for temperature below the superconducting transition temperature. Further, the Peltier cooling effect is observed for a wide range of parameter regimes, which can be optimized by varying the background thermal energy, QD level energy, QD-reservoir tunneling strength, and bias voltage. The results presented in this study are within the scope of existing experimental capabilities for designing miniature hybrid devices that operate at cryogenic temperatures. [ABSTRACT FROM AUTHOR]

Atomically thick two‐dimensional transition metal dichalcogenides (TMDs) have been extensively studied as optoelectronic materials because of their distinctive electronic structures and outstanding photonic and catalytic properties. In particular, when the size of TMDs are decreased to the quantum scale, they possess wider bandgaps and higher surface‐to‐volume ratios with more active edge sites per unit mass. Hence, they are promising for use in sensor, battery, and electrocatalytic applications. In this study, we briefly review the various popular synthesis methods of TMD quantum dots (QDs) from top‐down and bottom‐up approaches. Then, we summarize the optical, electronic, and catalytic properties of TMD QDs. Furthermore, recent progress on electrochemistry, energy storage, and solar cell applications of TMD QDs is summarized in detail. Finally, we summarize current research bottlenecks of TMD QDs and discuss potential avenues for future research. [ABSTRACT FROM AUTHOR]

Human norovirus (HuNoV) is the most predominant viral agents of acute gastroenteritis. Point‐of‐care testing (POCT) based on lateral flow immunochromatography (LIFC) has become an important tool for rapid diagnosis of HuNoVs. However, low sensitivity and lack of quantitation are the bottlenecks of traditional LIFC. Thus, we established a rapid and accurate technique that combined immunomagnetic enrichment (IM) with LFIC to identify GII HuNoVs in fecal specimens. Before preparing immunofluorescent nanomagnetic microspheres and achieving the effect of HuNoV enrichment in IM and fluorescent signal in LFIC, amino‐functionalized magnetic beads (MBs) and carboxylated quantum dots (QDs) were coupled at a mass ratio of 4:10. Anti‐HuNoV monoclonal antibody was then conjugated with QDs‐MB. The limit of detection was 1.56 × 104 copies/mL, and the quantitative detection range was 1.56 × 104 copies/mL–1 × 106 copies/mL under optimal circumstances. The common HuNoV genotypes GII.2, GII.3, GII.4, and GII.17 can be detected, there was no cross‐reaction with various enteric viruses, including rotavirus, astrovirus, enterovirus, and sapovirus. A comparison between IM‐LFIC and RT‐qPCR for the detection of 87 fecal specimens showed a high level of agreement (kappa = 0.799). This suggested that the method is rapid and sensitive, making it a promising option for point‐of‐care testing in the future. [ABSTRACT FROM AUTHOR]

With the growing trend in the information industry, silicon photonics technology has been explored in both academia and industry and utilized for high-bandwidth data transmission. Thanks to the benefits of silicon, such as high refractive index contrast with its oxides, low loss, substantial thermal–optical effect, and compatibility with CMOS, a range of passive and active photonic devices have been demonstrated, including waveguides, modulators, photodetectors, and lasers. The most challenging aspect remains to be the on-chip laser source, whose performance is constrained by the indirect bandgap of silicon. This review paper highlights the advancements made in the field of integrated laser sources on the silicon photonics platform. These on-chip lasers are classified according to their gain media, including V semiconductors, III–V semiconductors, two-dimensional materials, and colloidal quantum dots. The methods of integrating these lasers onto silicon are also detailed in this review. [ABSTRACT FROM AUTHOR]

Strong coupling of quantum states with electromagnetic modes of topological matter offer an interesting platform for the exploration of new physics and applications. In this work, we report a novel hybrid mode, a surface topological plexciton, arising from strong coupling between the surface topological plasmon mode of a Bi 2 Se 3 topological insulator nanoparticle and the exciton of a two-level quantum emitter. We study the power absorption spectrum of the system by working within the dipole and rotating-wave approximations, using a density matrix approach for the emitter, and a classical dielectric-function approach for the topological-insulator nanoparticle. We show that a Rabi-type splitting can appear in the spectrum suggesting the presence of strong coupling. Furthermore, we study the dependence of the splitting on the separation of the two nanoparticles as well as the dipole moment of the quantum emitter. These results can be useful for exploring exotic phases of matter, furthering research in topological insulator plasmonics, as well as for applications in the far-infrared and quantum computing. [ABSTRACT FROM AUTHOR]

Biosynthesized semiconductor quantum dots (QDs) have bright fluorescence, adjustable particle sizes, and environmental friendliness, endowing them with convenience and potential for biological applications. Due to the unclear mechanism of the cellular environment on the live-cell synthesis of QDs, it is still difficult to regulate their optical properties. Here, the critical role of the intracellular redox environment in regulating the fluorescence properties of biosynthesized CdSe QDs in Staphylococcus aureus (S. aureus) has been elucidated. The glutathione peroxidase (GPx) activity directly affects the intracellular H2O2 produced in the SeO32− reduction, which further manipulates the glutathione redox cycle to determine the content of low-valence Se-intermediates. As a result, the fluorescence intensity of the synthesized CdSe QDs increases by 60% in the GPx overexpressed cells. The cellular redox potential that is controlled by the GSH redox cycle provides the driving force for the reduction of SeO32−, facilitating the synthesis of CdSe QDs in S. aureus cells. The proposed mechanism of the cellular redox state provides a new perspective for regulating the synthesis of semiconductor nanomaterials in live cells. [ABSTRACT FROM AUTHOR]

Abstract The rapid development of emerging technologies observed in recent years, such as artificial intelligence, machine learning, mobile internet, big data, cloud computing, and the Internet of Everything, are generating escalating demands for expanding the capacity density, and speed in next‐generation optical communications. This poses a significant challenge to existing communication techniques. Within this context, the integration of near‐infrared broadband, tunable, and high‐gain luminescent materials into silicon optical circuits or fiber architectures to transmit and modulate light shows enormous potential for advancing next‐generation communication techniques. Here, this review provides an overview of the recent breakthroughs in near‐infrared luminescent epitaxial/colloidal quantum dots, and metal‐active‐center‐doped materials for broadband optical amplifiers and tunable lasers. We also expound on efforts to enhance the bandwidth and gain of these materials‐based amplifiers and lasers, exploring the challenges associate with developing ultra‐broadband and high‐speed optical communication systems. Additionally, the potential applications in Fifth Generation Fixed Networks, integration with 5G and 6G wireless networks, compensation for current Si electronic based CMOS for high computing capability, and the prospects of these light sources for next‐generation optoelectronic devices are discussed.

This study compares how a modified distributed Bragg reflector (DBR) and yellow color filter (Y-CF) increase the color purity, viewing angle, and brightness of the quantum dot color conversion layer (QDCC) for micro-LED displays. We designed and built a 53-layer high-performance modified DBR with almost total blue leakage filtering (T %: 0.16 %) and very high G/R band transmittance (T %: 96.97 %) for comparison. We also use a Y-CF that filters blue light (T %: 0.84 %) and has good G/R band transmittance (T %: 94.83 %). Due to DBR's angle dependency effect, the modified DBR/QDCC structure offers a remarkable color gamut (117.41 % NTSC) at the forward viewing angle, but this rapidly diminishes beyond 30°. The Y-CF/QDCC structure retains 116 % NTSC color at all viewing angles. Because of its consistent color performance at all viewing angles, sufficient brightness, and outstanding color gamut, the Y-CF/QDCC structure is the best option for contemporary QDCC-based micro-LED displays.

Abstract For the first time, a novel mercaptosuccinic acid‐capped tungsten telluride quantum dot (MSA‐WTe3‐QD)‐based electrochemical aptasensor was designed for the determination of SARS‐CoV‐2 N‐protein in synthetic human serum, plasma and urine. The MSA‐WTe3‐QD which exhibited spherical morphology and an average diameter of 3.56 nm were synthesized through a bottom‐up approach. The aptasensor was prepared by firstly immobilizing MSA‐WTe3‐QD on a screen‐printed carbon electrode (SPCE) by using the 1‐ethyl‐3‐(3‐dimethylaminopropyl)carbodiimide/N‐hydroxysuccinimide (EDC/NHS) coupling chemistry. Thereafter, amine‐terminated 90‐mer ssDNA aptamer was deposited on the modified SPCE and left to cure to form the aptasensor. Using the chronocoulometry signal transduction technique, the aptasensor's calibration with N‐protein gave a linear range value of 1–9 pg.mL−1 and a limit of detection (LOD) value of 0.08 pg.mL−1. The LOD value of the aptasensor was 8 times lower than the LOD value of 0.71 pg.mL−1 obtained with a commercial N‐protein ELISA kit. When tested in simulated real samples the aptasensor recovery rates of 95–103.33 % were obtained. In the presence of various interferents, the aptasensor displayed good selectivity to N‐protein.

While other works use segments of nonlinear crystal to compensate for walk-off, this work utilizes a quantum dot (QD) nanostructure for such compensation. Such nanocrystal structures allow two benefits: the high nonlinear susceptibility in these nanocrystals and the high surface density of QDs in the structure. Good results are obtained for pre-chirping and modulation parameters. The results are computed at 10 and 100 kV/cm applied electric fields. Compared to ordinary nonlinear crystals, the pulse width, intensity, and efficiency of the second harmonic (SH) pulse are all higher in QD nanocrystals, even with a low electric field applied. Higher applied fields give higher results.

Strong coupling of quantum states with electromagnetic modes of topological matter offer an interesting platform for the exploration of new physics and applications. In this work, we report a novel hybrid mode, a surface topological plexciton, arising from strong coupling between the surface topological plasmon mode of a Bi2Se3 topological insulator nanoparticle and the exciton of a two-level quantum emitter. We study the power absorption spectrum of the system by working within the dipole and rotating-wave approximations, using a density matrix approach for the emitter, and a classical dielectric-function approach for the topological-insulator nanoparticle. We show that a Rabi-type splitting can appear in the spectrum suggesting the presence of strong coupling. Furthermore, we study the dependence of the splitting on the separation of the two nanoparticles as well as the dipole moment of the quantum emitter. These results can be useful for exploring exotic phases of matter, furthering research in topological insulator plasmonics, as well as for applications in the far-infrared and quantum computing.

Abstract Tetragonal graphene nano-capsule (TGC), a novel stable carbon allotrope of sp2 hybridization is designed and doped with phosphorus (P) to study the O3 and SO2 gas sensitivity via density functional theory calculation. Real frequencies verified the natural existence of both TGC and P-doped TGC (PTGC). Both TGC and PTGC suffer structural deformations due to interaction with O3 and SO2 gases. The amount of charge transfer from the adsorbent to the gas molecule is significantly greater for O3 adsorption than SO2 adsorption. The adsorption energies for TGC + O3 and PTGC + O3 complexes are − 3.46 and − 4.34 eV respectively, whereas for TGC + SO2 and PTGC + SO2 complexes the value decreased to − 0.29 and − 0.30 eV respectively. The dissociation of O3 is observed via interaction with PTGC. A significant variation in electronic energy gap and conductivity results from gas adsorption which can provide efficient electrical responses via gas adsorption. The blue/red shift in the optical response proved to be a way of detecting the types of adsorbed gases. The adsorption of O3 is exothermic and spontaneous whereas the adsorption of SO2 is endothermic and non-spontaneous. The negative change in entropy verifies the thermodynamic stability of all the complexes. QTAIM analysis reveals strong covalent or partial covalent interactions between absorbent and adsorbate. The significant variation in electrical and optical response with optimal adsorbent-gas interaction strength makes both TGC and PTGC promising candidates for O3 and SO2 sensing.

Micro-light-emitting diodes (micro-LEDs) with outstanding performance are promising candidates for next-generation displays. To achieve the application of high-resolution displays such as meta-displays, virtual reality, and wearable electronics, the size of LEDs must be reduced to the micro-scale. Thus, traditional technology cannot meet the demand during the processing of micro-LEDs. Recently, lasers with short-duration pulses have attracted attention because of their unique advantages during micro-LED processing such as noncontact processing, adjustable energy and speed of the laser beam, no cutting force acting on the devices, high efficiency, and low cost. Herein, we review the techniques and principles of laser-based technologies for micro-LED displays, including chip dicing, geometry shaping, annealing, laser-assisted bonding, laser lift-off, defect detection, laser repair, mass transfer, and optimization of quantum dot color conversion films. Moreover, the future prospects and challenges of laser-based techniques for micro-LED displays are discussed.

This study develops a novel high‐thickness BM QD color conversion layer structure and a surface‐planarization process for QD materials after inkjet printing. This process reduces the height differences caused by the multi‐step exposure‐developing process. Following the fabrication of 8μm BM structure and 2μm CF structure, precise inkjet printing of QD materials is conducted within the 100ppi pixel area. we adjusted the surface energy of the color conversion layer by using an organic solution treatment to control the thickness profile and improve the color conversion efficiency. The printed QD materials are covered by a high‐transparency, low‐density polymer. After the color conversion layer component is encapsulated, reliability verification with a reliability assessment of 240 hours at RA (60℃ degrees, 90%RH) demonstrates an encapsulation effect where QD brightness retention rate remains above 90%. [ABSTRACT FROM AUTHOR]

We report and discuss the challenges to realize a nanoLED based display from the perspective of materials and processes. Additionally, we report on a 30‐inch 4K active‐matrix nanoLED display using cadmium free Quantum Dots (QDs) patterned by photolithography in the atmosphere. [ABSTRACT FROM AUTHOR]

Both phosphors and quantum dots are currently used in liquid crystal displays (LCDs), with GE's KSF narrow red phosphor demonstrating the best possible red color point, reliability, and efficiency. Next generation miniLED and microLED based displays require excellent color quality (gamut) and high brightness which will require color conversion materials with high EQE and narrow emission peaks. Here we describe recent advancements in submicron narrow‐band phosphors which are being implemented in next‐generation miniLED displays, and being considered for enabling full‐color microLED and luminescent color filter displays of the future due to their excellent optical performance and robust nature. [ABSTRACT FROM AUTHOR]

Despite the existing effective treatment methods, tuberculosis (TB) is the second most deadly infectious disease, its carriers in the latent and active phases accounting for more than 20% of the world population. An effective method for controlling TB and reducing TB mortality is regular population screening aimed at diagnosing the latent form of TB and taking preventive and curative measures. Numerous methods allow diagnosing TB by directly detecting Mycobacterium tuberculosis (M.tb) biomarkers, including M.tb DNA, proteins, and specific metabolites or antibodies produced by the host immune system in response to M.tb. PCR, ELISA, immunofluorescence and immunochemical analyses, flow cytometry, and other methods allow the detection of M.tb biomarkers or the host immune response to M.tb by recording the optical signal from fluorescent or colorimetric dyes that are components of the diagnostic systems. Current research in biosensors is aimed at increasing the sensitivity of detection, a promising approach being the use of fluorescent quantum dots as brighter and more photostable optical tags. Here, we review current methods for the detection of M.tb biomarkers using quantum dot-based nanosensors and summarize data on the M.tb biomarkers whose detection can be made considerably more sensitive by using these sensors.

Memristor devices for resistive-switching memory and artificial synapses have emerged as promising solutions for overcoming the technological challenges associated with the von Neumann bottleneck. Recently, due to their unique optoelectronic properties, solution processability, fast switching speeds, and low operating voltages, quantum dots (QDs) have drawn substantial research attention as candidate materials for memristors and artificial synapses. This review covers recent advancements in QD-based resistive random-access memory (RRAM) for resistive memory devices and artificial synapses. Following a brief introduction to QDs, the fundamental principles of the switching mechanism in RRAM are introduced. Then, the RRAM materials, synthesis techniques, and device performance are summarized for a relative comparison of RRAM materials. Finally, we introduce QD-based RRAM and discuss the challenges associated with its implementation in memristors and artificial synapses.