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Free space optical communication with infrared light is a promising secure wireless optical communication technology, where infrared photodetectors are the core component. To date, such applications are based on epitaxial growth narrow‐band semiconductors facing the challenge of large‐area fabrication. Infrared colloidal quantum dots (CQDs) are of interest because of the high‐throughput solution processing. Here, large‐area CQD photodetectors with adjustable wavelengths covering 1.3–2.0 µm. For 1 × 1 mm2 CQD photodetector, the response time achieved within 1 µs at room temperature, responded sharply to the 25 kbps PRBS‐7 communication code is demonstrated. For 1.5 × 1.5 cm2 large‐area CQD photodetectors, a communication rate of 2 kbps is achieved. This work is a step toward the CQD application in the field of optical communications. [ABSTRACT FROM AUTHOR]

The nonspecific nature of cancer drug delivery often results in substantial toxic side effects during treatments for breast cancer. To mitigate these negative outcomes, our approach involves loading methotrexate (MTX) within carbon quantum dots (CQDs) synthesized from folic acid, which are then enveloped in exosomal membranes obtained from breast cancer cells (Ex@MTX-CQDs). Analysis utilizing nanoparticle tracking techniques has demonstrated that these Ex@MTX-CQDs maintain the physical and biochemical properties of their exosomal precursors. The release profile of MTX indicated a restricted release percentage (less than 10%) under normal physiological conditions, which is contrasted by a more consistent release rate (approximately 65%) when emulating the conditions found within tumor tissues. The toxicological assessments have confirmed that the presence of exosomes combined with leftover folic acid significantly improves the delivery efficacy of MTX directly to the cancerous cells through the binding to folate and heparan sulfate proteoglycan receptors. This process results in increased disruption of the mitochondrial membrane potential and subsequently triggers apoptosis, ultimately leading to the destruction of cancerous cells. Our research could potentially contribute to the further innovation and application of nanocarriers derived from biological sources for the targeted treatment of breast cancer. [ABSTRACT FROM AUTHOR]

The effective conversion of carbon dioxide (CO2) into valuable chemical fuels relies significantly on the donation of multiple electrons. Its efficiency is closely linked to both the density and lifetime of excited charge carriers. In this study, a hybrid catalyst system comprising covalently bonded InP/ZnS quantum dots (QDs) and Re‐complexes is showcased. The electronic band alignment between the QDs and the Re‐complexes is revealed to dominate the multi‐electron transfer process for photocatalytic conversion to methane (CH4). Notably, the size of the QDs is found to be a determining parameter. Among the three QD sizes investigated, transient absorption spectroscopy studies unveil that rapid multi‐electron transfer from the QDs to the Re‐catalyst occurs in smaller QDs (2.3 nm) due to the substantial driving force. Consequently, the photocatalytic conversion of CO2 to CH4 is significantly enhanced with a turnover number of 6, corresponding to the overall apparent quantum yield of ≈1%. This research underscores the possibilities of engineering multi‐electron transfer by manipulating the electronic band alignment within a catalytic system. This can serve as a guide for optimizing photocatalytic CO2 reduction. [ABSTRACT FROM AUTHOR]

We study the electron tunneling (ET) and local Andreev reflection (AR) processes in a quantum dot (QD) coupled to the left and right ferromagnetic leads with noncollinear ferromagnetisms. In particular, we consider that the QD is also side-coupled to a nanowire hosting Majorana bound states (MBSs) at its ends. Our results show that when one mode of the MBSs is coupled simultaneously to both spin-up and spin-down electrons on the QD, the height of the central peak is different from that if the MBS is coupled to only one spin component electrons. The ET and AR conductances, which are mediated by the dot–MBS hybridization, strongly depend on the angle between the left and right magnetic moments in the leads. Interaction between the QD and the MBSs will result in sign change of the angle-dependent tunnel magnetoresistance. This is very different from the case when the QD is coupled to regular fermonic mode, and can be used for detecting the existence of MBSs, a current challenge in condensed matter physics under extensive investigations. [ABSTRACT FROM AUTHOR]

Strain-free GaAs cone-shell quantum dots have a unique shape, which allows a wide tunability of the charge-carrier probability densities by external electric and magnetic fields. Here, the influence of a lateral electric field on the optical emission is studied experimentally using simulations. The simulations predict that the electron and hole form a lateral dipole when subjected to a lateral electric field. To evaluate this prediction experimentally, we integrate the dots in a lateral gate geometry and measure the Stark-shift of the exciton energy, the exciton intensity, the radiative lifetime, and the fine-structure splitting (FSS) using single-dot photoluminescence spectroscopy. The respective gate voltage dependencies show nontrivial trends with three pronounced regimes. We assume that the respective dominant processes are charge-carrier deformation at a low gate voltage U, a vertical charge-carrier shift at medium U, and a lateral charge-carrier polarization at high U. The lateral polarization forms a dipole, which can either enhance or compensate the intrinsic FSS induced by the QD shape anisotropy, dependent on the in-plane orientation of the electric field. Furthermore, the data show that the biexciton peak can be suppressed by a lateral gate voltage, and we assume the presence of an additional vertical electric field induced by surface charges. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This study presents a novel photodiode technology with augmented optoelectronic capabilities through the incorporation of quantum dots (QDs). The photodiode, composed of Indium Gallium Zinc Oxide‐Tellurium (IGZO‐Te), is engineered for enhanced light sensitivity and tailored optoelectronic interactions. The primary application of this advanced photodiode lies in the domain of artificial intelligence and machine learning, where it plays a pivotal role in simulating synaptic connections for image processing tasks. Due to the exceptional optical and electrical properties of the IGZO‐Te‐QDs active material combination, the photodiode demonstrates consistent and dependable optical synaptic functions linked to learning. This is achieved through conduction modulation and time duration modulation of light stimulus. In addition, the opto‐synaptic functionalities such as short‐term and long‐term memory has also been successfully demonstrated not only on single device but also on 6 × 6 photodiodes array device. These findings underscore the significant potential of the hybrid structure of IGZO‐Te with QDs in optical artificial neuromorphic chips. [ABSTRACT FROM AUTHOR]

CdS quantum dots (QDs) are widely employed as photocatalysts for reactions such as hydrogen evolution, and their degradation under aerobic aqueous conditions is well understood. However, despite evidence of aggregation and precipitation of CdS QD photocatalysts under anaerobic conditions, catalyst speciation and degradation under such conditions are underexplored. In this work, we demonstrate that during a reductive dehalogenation reaction, CdS QDs undergo surface ligand etching, which leads to a loss of colloidal stability and the formation of microcrystalline cadmium metal deposits. We hypothesize that this results from the accumulation of electrons on the QD surface. In addition, we demonstrate mild surface sulfur oxidation and the formation of an ammonium salt byproduct of a commonly used hole quencher. This work adds to our atomic-level understanding of the reactions occurring at the QD surface during photocatalysis, so that we can design more stable and efficient photocatalysts for organic synthesis. [ABSTRACT FROM AUTHOR]

We study the confinement of a quantum particle to the squared cotangent potential in the background of global monopole spacetime. By dealing with s-states, we obtain the energy levels from the exact solutions to the Schrödinger equation. Then, we show that the topology of the global monopole spacetime influences the energy levels. Further, we show that there is a non-null revival time with regard to the squared cotangent potential and how it is influenced by the global monopole topology. [ABSTRACT FROM AUTHOR]

Quantum dots currently possess significant importance in the field of biomedical science. Upon introduction into the body, quantum dots exhibit a tendency to accumulate in diverse tissues including the central nervous system (CNS). Consequently, it becomes imperative to devote specific attention to their potential toxic effects. Moreover, the preservation of optimal CNS function relies heavily on blood–brain barrier (BBB) integrity, thereby necessitating its prioritization in neurotoxicological investigations. A more comprehensive understanding of the BBB and CNS characteristics, along with the underlying mechanisms that may contribute to neurotoxicity, will greatly aid researchers in the development of effective design strategies. This article offers an in‐depth look at the methods used to reduce the harmful effects of quantum dots on the nervous system, alongside the progression of effective treatments for brain‐related conditions. The focal point of this discussion is the BBB and its intricate association with the CNS and neurotoxicology. The discourse commences by recent advancements in the medical application of quantum dots are examined. Subsequently, elucidating the mechanisms through which quantum dots infiltrate the human body and traverse into the brain. Additionally, the discourse delves into the factors that facilitate the passage of quantum dots across the BBB, primarily encompassing the physicochemical properties of quantum dots and the BBB's inherent capacity for self‐permeability alteration. Furthermore, a concluding summary is presented, emphasizing existing research deficiencies and identifying promising avenues for further investigation within this field. This article explores quantum dots' biomedical applications, emphasizing their potential neurotoxicity and impact on the blood‐brain barrier (BBB). It discusses methods to mitigate quantum dots' harmful effects on the nervous system and highlights advancements in brain‐related treatments. The focus is on understanding BBB integrity, quantum dots' mechanisms of entry into the CNS, and factors influencing their passage across the barrier. The conclusion underscores research gaps and suggests future avenues for investigation in this field. [ABSTRACT FROM AUTHOR]

Carbon quantum dots (CQDs) were prepared by electro-chemical reaction method under reaction conditions such as time and current. The current is 30 mA and time is 3 h. The samples were analyzed using X-ray diffraction, transmission electron microspectroscopy, Fourier transform infrared spectroscopy, photoluminescence spectroscopy, UV–visible spectroscopy, and Hall effect. The results showed that the crystal size calculated by Debye–Scherrer's formula was 70 nm and a greater peak of 1577 cm−1 obtained from FTIR corresponded to C꞊C, which refers to CQDs. The generated energy surface state was measured, which is 3.17, 2.54, 2.33, and 2.01 eV, and the change in the size of surface state was measured, which is 3.372, 3.089, 2.891, and 2.685 nm, respectively, and the free carrier concentration was 5.008 × 108 cm−2, where it was the nanostructure. It was found by measuring the Hall effect that the CQDs were p-type. [ABSTRACT FROM AUTHOR]

In the filtered optical feedback system, a part of the emission of the laser is spectrally filtered, here by a Fabry–Perot (FP) filter, and then fed back into the quantum-dot (QD) laser cavity. This technique has been used in various applications such as inducing frequency dynamics in QD semiconductor lasers and studying the dynamical behavior of a QD semiconductor laser subject to delayed filtered optical feedback. We report on the systematical investigation of the steady-state regime and the dynamical behavior of a QD semiconductor laser subject to delayed FOF. The effects of the filter on the locking of the QD laser frequency to the external cavity modes are described. We report and observe hysteresis, bistability, and multistability and show that all these are well described by a set of rate equations for the coupled QD laser and FP cavity system. We also present a stability diagram that summarizes the dynamical behavior of the system. [ABSTRACT FROM AUTHOR]

Traditional quantum dot-based lateral flow immunoassay (QD-LFIA) is limited to signal loss in part by the blinking, photobleaching and oxidative quenching of QD probes. Inspired by the good application of silver deposition on QD surfaces in tissue imaging, and in the context of improving the assay performance without compromising the simplicity and practicality, we report that introducing the QD-silver combination to the LFIA system, has the advantages of accuracy improvement, signal enhancement and user friendliness promotion, but maintains the cost-effective property and commercial accessibility of QD-LFIA. The effect was shown by using CdSe/ZnS QD-LFIA coupled with anti-sodium pentachlorophenate antibody, which provided a 4-fold improvement in the signal, a 2.5-fold improvement in the detection limit and a zero false-negative rate for sodium pentachlorophenate analysis in chicken samples. The proposed LFIA integrates the possibilities of colorimetric and fluorometric detection with different detection limits (fluorometric at 10 ng/mL and colorimetric at 4 ng/mL) and with acceptable detection times (fluorometric at 12 min and colorimetric at 27 min). The current results indicate that this QD-silver combined LFIA is complementary to conventional fluorescence LFIA and could be an inexpensive, versatile, and sensitive alternative.

The synthesis of compounds via conventional thermochemical methods necessitates reactions at high temperatures and pressures, which results in significant energy consumption and carbon dioxide emissions. Moreover, the fabrication of compounds with intricate structures frequently faces obstacles in attaining high levels of purity. These challenges associated with chemical synthesis could potentially be supplanted by biological synthesis methods, which operate under benign conditions and exhibit exceptional selectivity. Nonetheless, a primary limitation of biological chemical synthesis is its inherently low productivity, rendering it less competitive relative to chemical methodologies and difficult to implement in actual industrial settings. To overcome these obstacles, extensive research is being undertaken to develop quantum dot-biohybrid (QD-biohybrid) systems. Quantum dots (QDs) are semiconductor nanocrystals capable of absorbing light and generating photo-excited electrons, making them suitable as photosensitizers. Upon light irradiation of the QD-biohybrid system, the quantum dots within the hybrid structure absorb the light, and the resulting photo-excited electrons are transferred to enzymes, thereby enhancing biochemical productivity. This review highlights the progress in the field where various inorganic nanoparticles (NPs) are combined with microorganisms or enzymes within hybrid structures, focusing on their efficacy in synthesizing a range of compounds. This review will explore analytical techniques that elucidate these systems’ construction and operational mechanisms to establish a scientific foundation for further investigation. The challenges this innovative chemical synthesis platform faces are delineated, particularly the degradation of the biosystems, and ongoing strategies to mitigate these issues are discussed. Ultimately, the scalability of the QD-biohybrid system for practical industrial applications will be assessed.

ABSTRACTMicrospheres composed of Y-containing materials are effective agents for cancer radioembolization therapy using β-rays. The distribution and dynamics of these microspheres in tissues can be easily determined by providing the microspheres with an imaging function. In addition, the use of quantum dots will enable the detection of microspheres at the individual particle level with high sensitivity. In this study, core – shell quantum dots were bound to chemically modified yttria microspheres under various conditions, and the effect of reaction conditions on the photoluminescence properties of the microspheres was investigated. The quantum dots were immobilized on the surfaces of the microspheres through dehydration – condensation reactions between the carboxy groups of quantum dots and the amino groups of silane-treated microspheres. As the reaction time increased, the photoluminescence peak blue shifted, and the photoluminescence intensity and lifetime decreased. Therefore, a moderate period of the immobilization process was optimal for imparting effective photoluminescence properties. This study is expected to facilitate particle-level tracking of microsphere dynamics in biological tissues for the development of minimally invasive cancer radiotherapy of deep-seated tumors.

Critical illness myopathy (CIM) detrimentally affects muscle function in ICU patients, with a dramatic loss of muscle mass and function where the loss in specific force exceeds the loss in muscle mass (maximum force normalized to muscle cross-sectional area). The preferential loss of the molecular motor protein myosin, representing the hallmark of CIM, exhibiting a significant negative impact on the specific force generation by the muscle. Interestingly however, the preferential myosin loss is a relatively late event, and a specific loss in force generation capacity, is observed prior to the myosin loss. In the current study, employing an optimized cadmium telluride quantum dots (QD) mediated-thermometry approach to assess the efficiency of the myosin, we were able to determine the loss in specific force generated by the muscle, prior to the preferential loss of myosin. Reduction in QD fluorescent intensity correlates with greater heat loss, reflecting inefficient myosin function (less mechanical work performed and more heat loss on ATP hydrolysis by myosin). A significant decrease in myosin efficiency was observed in rats subjected to the ICU condition (immobilization and mechanical ventilation) for 5 days using an established experimental ICU model not limited by early mortality. Thus, qualitative myosin changes preceding quantitative myosin loss offer a mechanism underlying the early loss in specific force generation capacity associated with CIM and opens a venue for future CIM intervention strategies.

Near-infrared photodetectors were fabricated by incorporating formamidinium lead iodide (FAPbI3) quantum dots (QDs) as the light-harvesting layer. Through systematic optimization of the device architecture, high device performance was achieved by utilizing PCBM as the electron transport material and a 50 nm-thick TAPC film as the hole transport layer. The energy level alignment between PCBM and the FAPbI3 QDs enabled efficient exciton dissociation and hole blocking, while the optimized TAPC thickness decrease current leakage pathways. The resulting photodetectors exhibited an impressive external quantum efficiency of 59.56 % at 750 nm, along with a high specific detectivity of 2.63 x 1011 Jones. A broadband photoresponse from 300–900 nm was observed, as well as a fast temporal response with 30.58/31.26 μs rise/fall times. A substantial linear dynamic range of 61.5 dB was achieved under 780 nm illumination. Furthermore, the low dark current densities facilitated by the judiciously selected materials and thicknesses contributed to the excellent overall device performance. The device performance of the PCBM/FAPbI3 QDs/TAPC system demonstrate its promising potential for near-infrared optoelectronic applications requiring high sensitivity, speed, and broad spectral response, opening up opportunities for further advances in photodetection as well as other relevant device technologies.

Abstract 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.

The growing demand for wearable and attachable displays has sparked significant interest in flexible quantum-dot light-emitting diodes (QLEDs). However, the challenges of fabricating and operating QLEDs on flexible substrates persist due to the lack of stable and low-temperature processable charge-injection/-transporting layers with aligned energy levels. In this study, we utilized NiOx nanoparticles that are compatible with flexible substrates as a hole-injection layer (HIL). To enhance the work function of the NiOx HIL, we introduced a self-assembled dipole modifier called 4-(trifluoromethyl)benzoic acid (4–CF3–BA) onto the surface of the NiOx nanoparticles. The incorporation of the dipole molecules through adsorption treatment has significantly changed the wettability and electronic characteristics of NiOx nanoparticles, resulting in the formation of NiO(OH) at the interface and a shift in vacuum level. The alteration of surface electronic states of the NiOx nanoparticles not only improves the carrier balance by reducing the hole injection barrier but also prevents exciton quenching by passivating defects in the film. Consequently, the NiOx-based red QLEDs with interfacial modification demonstrate a maximum current efficiency of 16.1 cd/A and a peak external quantum efficiency of 10.3%. This represents a nearly twofold efficiency enhancement compared to control devices. The mild fabrication requirements and low annealing temperatures suggest potential applications of dipole molecule-modified NiOx nanoparticles in flexible optoelectronic devices. [ABSTRACT FROM AUTHOR]

The study aims to create a highly responsive gas sensor for TEA. In order to achieve this goal, spherical ZnO with layered structure was synthesized by a simple hydrothermal method. Subsequently, Ag quantum dots (QDs) are precipitated onto the surface of the ZnO microspheres. The ZnO microspheres were analyzed to demonstrate that they are comprised of porous nanosheets measuring roughly 10 μm in diameter. The composite with the optimal mass percentage displayed outstanding sensitivity to triethylamine (TEA), yielding a response of 1223, approximately 90 times higher than that of the pure ZnO sensor. Furthermore, this composite also demonstrated remarkable selectivity towards TEA. The exceptional detection results were achieved due to the catalytic influence of Ag as a precious metal, coupled with the distinctive structure of quantum dots and ZnO materials. [ABSTRACT FROM AUTHOR]

The 2023 Nobel Prize in Chemistry was awarded to Aleksey I. Ekimov (prize share 1/3), Louis E. Brus (prize share 1/3), and Moungi G. Bawendi (prize share 1/3) for groundbreaking inventions in the field of nanotechnology, i.e., for the discovery and synthesis of semiconductor nanocrystals, also termed quantum dots, that exhibit size-dependent physicochemical properties enabled by quantum size effects. This feature article summarizes the main milestones of the discoveries and developments of quantum dots that paved the road to their versatile applications in solid-state lighting, display technology, energy conversion, medical diagnostics, bioimaging, and image-guided surgery. [ABSTRACT FROM AUTHOR]

Accurate and sensitive analysis of cancer‐associated microRNAs in living tissue is of great significance for the early diagnosis and treatment of cancer. Herein, a hierarchical nanoprobe denoted as UCNP‐QDs‐GNPs is delicately designed, where a near‐infrared (NIR) absorptive upconversion nanoparticle (UCNP) serves as the core, broad‐absorptive and bright emissive quantum dots (QDs) and emission‐quencher gold nanoparticles (GNPs) surround as satellites for microRNA imaging and image‐guided cancer therapy. Through the programmed assembly of heterobivalent DNA‐conjugated QDs with DNA‐modified GNPs and UCNPs, the well‐defined nanostructured UCNP‐QDs‐GNPs are generated with quenched fluorescence. Upon encountering the microRNA‐21 target, GNPs underwent catalytic disassembly, resulting in the concurrent recovery and amplification of fluorescence from QDs and UCNPs, which enabled sensitive imaging and quantification of microRNA‐21 within living cells. Furthermore, dithiol‐constituted aggregation‐induced emission (AIE) photosensitizers bonded on the surface of QDs, are effectively photosensitized by the QDs. The NIR excitation harvested by UCNPs is therefore efficiently transferred to QDs and subsequently converged on the AIE photosensitizers, boosting photodynamic activity for image‐guided therapy in deep‐seated tumors. The DNA‐programmed (de)hybridization strategy, facilitating the conversion of NIR excitation into imaging signals and photodynamic activity, offers a promising avenue for the early theranostics of malignancies. [ABSTRACT FROM AUTHOR]

Micro-light-emitting diodes (μLEDs), with their advantages of high response speed, long lifespan, high brightness, and reliability, are widely regarded as the core of next-generation display technology. However, due to issues such as high manufacturing costs and low external quantum efficiency (EQE), μLEDs have not yet been truly commercialized. Additionally, the color conversion efficiency (CCE) of quantum dot (QD)-μLEDs is also a major obstacle to its practical application in the display industry. In this review, we systematically summarize the recent applications of nanomaterials and nanostructures in μLEDs and discuss the practical effects of these methods on enhancing the luminous efficiency of μLEDs and the color conversion efficiency of QD-μLEDs. Finally, the challenges and future prospects for the commercialization of μLEDs are proposed. [ABSTRACT FROM AUTHOR]

Many different types of nanoparticles have been suggested for tumor-targeted theranosis. However, most systems were prepared through a series of complicated processes and could not even overcome the blood–immune barriers. For the accurate diagnosis and effective treatment of cancers, herein we suggested the lipid micellar structure capturing quantum dot (QD) for cancer theranosis. The QD/lipid micelles (QDMs) were prepared using a simple self-assembly procedure and then conjugated with anti-epidermal growth factor receptor (EGFR) antibodies for tumor targeting. As a therapeutic agent, Bcl2 siRNA-cholesterol conjugates were loaded on the surface of QDMs. The EGFR-directed QDMs containing Bcl2 siRNA, so-called immuno-QDM/siBcl2 (iQDM/siBcl2), exhibited the more effective delivery of QDs and siBcl2 to target human colorectal cancer cells in cultures as well as in mouse xenografts. The effective in vivo targeting of iQDM/siBcl2 resulted in a more enhanced therapeutic efficacy of siBcl2 to the target cancer in mice. Based on the results, anti-EGFR QDM capturing therapeutic siRNA could be suggested as an alternative modality for tumor-targeted theranosis. [ABSTRACT FROM AUTHOR]

The optoelectronic properties of quantum nanostructures are determined by their sizes and energy states affected by external electric field. The IR subband optical absorption of zinc-blende GaN/AlN spherical quantum dots (QDs) is obtained from perturbed energy states. The static dielectric constant and associated functions for broadened general absorption in the strong absorptive region are obtained from an improved iterative density matrix. These functions are also verified via Kramers–Kronig relations for a 4 nm zinc-blende GaN/AlN heterocrystal QD. The dielectric constants obtained for QDs in this study are well-matched with the bulk dielectric constant of GaN. Additionally, it is observed that the electric field effect dominates at the above of excitonic radius, while size effects significantly alter subband energies for smaller QD radius. As a perturbative result, forbidden transition-peaks in the presence of the electric field are also obtained at sizes of QD radii 5 nm and 6 nm. [ABSTRACT FROM AUTHOR]

In the research, the effects of the Rashba spin–orbit interaction (SOI) and magnetic field have been studied on the electronic and optical properties of a Frost–Musulin (FM) quantum dot. For this goal, the Schrödinger equation has been analytically solved by the Nikiforov–Uvarov (NU) procedure, and the energy states and the wave functions have been analytically derived. Using the analytical relations for optical properties, the total refractive index change (RIC) and absorption coefficient (AC) are calculated under a magnetic field with the Rashba SOI. The findings show that both the Rashba SOI and the magnetic field have a strong effect on the energy levels, RIC, and AC. The Rashba SOI causes the energy states to split into two branches, up and down. The peak locations of the RIC and AC move to higher energies when the magnetic field and Rashba coupling are increased. [ABSTRACT FROM AUTHOR]

This paper describes the recent advances in device designs and optical transmission applications of semiconductor optical amplifiers (SOA). The device advances described are quantum-dot-based SOA and photonic-integrated circuits using SOA. The use of nonlinear properties of SOAs in high-speed optical transmission is discussed. [ABSTRACT FROM AUTHOR]

The stationary states of an electron in a nanosized semiconductor quantum dot of spheroidal shape with a deep confining potential are considered. The discrete energy spectrum and corresponding wave functions are very sensitive to the elongation, especially in the region of high eccentricity values. The main attention is paid to identifying the patterns of the radial-angular distribution of electron wave functions, which should play an important role in the angular distribution of photons emitted by the quantum dot. [ABSTRACT FROM AUTHOR]

Gas sensors exhibit significant potential due to their widespread use in various applications, such as food packaging, indoor air quality assessment, and real-time monitoring of man-made gas emissions to mitigate global warming. The utilization of nanostructured materials for sensor and adsorbent surfaces has seen remarkable growth over time, though substantial efforts are still needed to develop more efficient adsorbents. Consequently, this study investigates the viability of metal-doped quantum dots (QDs) as prospective gas-sensing and adsorption materials. Density functional theory (DFT) calculations employing the 6-311 + G(d,p) basis set and three functionals (B3LYP, B3LYP-GD3(BJ), and ɷB97XD) were utilized for this investigation. Three environmentally and health-significant gases (C6H6, CO2, and H2S) were chosen as adsorbates on arsenic (As) and cobalt (Co) functionalized QDs to assess the performance and sensing capabilities of resulting QD surfaces. The analysis encompassed computation of adsorption energy, thermodynamic properties, non-covalent interactions, natural bond orbital analysis, and other topological aspects for both the surfaces and gases. The outcomes indicate that the GP_As functionalized surface exhibits a lower energy gap, rendering it more reactive and sensitive toward the respective gases (C6H6, CO2, and H2S). Moreover, the calculated adsorption energies of the investigated systems indicate thermodynamic favorability and spontaneity. Notably, our findings suggest that QD_As surfaces possess superior adsorption potential for H2S compared to the other gases examined; nonetheless, all studied QD surfaces demonstrate significant adsorption capacities for C6H6, CO2, and H2S gases. [ABSTRACT FROM AUTHOR]

Mixed-dimensional composite structures using zero-dimensional (0D) quantum dots (QDs) and two-dimensional (2D) transition metal dichalcogenides (TMDs) materials are expected to attract great interest in optoelectronics due to the potential to generate new optical properties. Here, we report on the unique optical characteristics of a devices with mixed dimensional vertically stacked structures based on tungsten diselenide (WSe2)/CdSeS QDs monolayer/molybdenum disulfide (MoS2) (2D/0D/2D). Specifically, it exhibits an ambipolar photoresponse characteristic, with a negative photoresponse observed in the 400–600 nm wavelength range and a positive photoresponse appeared at 700 nm wavelength. It resulted in the high negative responsivity of up to 52.22 mA·W−1 under 400 nm, which is 163 times higher than that of the photodetector without CdSeS QDs. We also demonstrated the negative photoresponse, which could be due to increased carrier collision probability and non-radiative recombination. Device modeling and simulation reveal that Auger recombination among the types of non-radiative recombination is the main cause of negative photocurrent generation. Consequently, we discovered ambipolar photoresponse near a specific wavelength corresponding to the energy of quantum dots. Our study revealed interesting phenomenon in the mixed low-dimensional stacked structure and paved the way to exploit it for the development of innovative photodetection materials as well as for optoelectronic applications. [ABSTRACT FROM AUTHOR]

This work adopts machine learning to refine the annealing process in solution‐processed thin films, such as QDs, perovskites, and organic semiconductors. The annealing temperature and time of PbS QD thin film is optimized using a machine learning algorithm. This method offers a systematic approach to determine the optimal annealing parameters, surpassing the traditional, less‐efficient methods. This adaptive model minimizes human bias, handles complex nonlinear relationships, and capable of optimizing multiple parameters simultaneously. By introducing machine learning algorithm, this method provides a universal and effective strategy for the optimization of parameters during the fabrication of thin films. [ABSTRACT FROM AUTHOR]

The nanoLED, an electroluminescent device utilizing quantum dots (QDs), is expected to be a promising candidate for the next‐generation display. This paper presents a newly developed QD protection technology for cadmium‐free nanoLEDs that enables simultaneous achievement of high‐efficiency electroluminescence (EL) and long lifetime. The device which was prototyped by applying ZnSeTe blue QDs to an emissive layer demonstrated a maximum external quantum efficiency (EQE) of 21.0% and a luminance half‐lifetime (LT50) of 128,000 hours at 100 nits. These results indicate that cadmium‐free nanoLEDs can meet the requirements for display application in terms of both EL efficiency and reliability. [ABSTRACT FROM AUTHOR]

This study proposes a mass production solution for quantum dot color converter (QDCC) of mid‐resolution micro‐LED displays. Therefore, a gray bank materials and QD photoresist (PR) with high optical density (OD) and low film thickness were developed. The gray bank materials can achieve OD = 1.08 and a reflectivity of over 25% at a thickness of 4 μm. The red QDPR has OD = 1.93 at 3 μm, and the green QDPR has OD = 1.58 at 3.3 μm. Finally, a 125 PPI and 7‐inch QDCC were fabricated using a G2.5 TFT‐LCD production line, and the optimal material formula and process conditions were determined. Optical analysis shows color point uniformity with STD < 1.3%, indicating that this solution can provide excellent in‐plane uniformity. [ABSTRACT FROM AUTHOR]