Device Stability Research Articles

Defects passivation in chloride-iodide perovskite solar cell with chlorobenzylammonium halides

Despite promising optoelectronic properties, it is a matter of fact that ion migration is unavoidable in chloride-iodide-based perovskite solar cells due to a radius mismatch between chlorine and iodine. Local defects like atomic vacancies or accumulation of atoms might occur due to ion migration in chloride-iodide-based perovskite thin film. Again, atomic vacancies are prevalent in solution-processed perovskite thin film. Here we have investigated the passivation of these defects with two organic halide passivators named 4-chlorobenzylammonium chloride and 4-chlorobenzylammonium bromide. They passivate both the surface and bulk of the perovskite thin film. The surface of the perovskite thin film is passivated with the bulky organic benzylammonium cations. The bulk of the perovskite thin film is passivated with the diffusion of chlorine or bromine. With different combinations of the two passivators, we vary the chlorine range from 50% to 100% and the bromine range from 25% to 50%. We have found the champion cell performance for 75% chlorine and 25% bromine combination. The enhancement of device efficiency was around 15% compared to the control device and the device stability was also considerably enhanced.

Synthesis and investigation of charge storage characteristics in Ni-MOF/PANI composite as an active electrode material for supercapacitor

This study aimed to develop a more stable and efficient energy storage device, synthesis of nickel-based pristine metal organic framework (MOF) and combined it with the emeraldine base phase of polyaniline (PANI) which is confirmed with XRD, SEM and TEM. Both Ni-MOF and PANI exhibit faradaic (battery-like) behaviour. However, when these two materials are combined, the stability of the resulting material is enhanced. The initial materials, MOF and PANI, exhibit specific capacities of 42 C/g and 72 C/g, respectively. However, when these two materials are combined, their composite exhibits an enhanced specific capacity of 122 C/g. The cyclic voltammetry (CV) analysis shows oxidation and reduction peaks, indicating faradaic behaviour. This behaviour is further confirmed by electrochemical impedance spectroscopy (EIS). Upon comparing it with prior results, the specific capacity appears to be slightly lower. However, it is anticipated to exhibit stronger stability, which is contradictory. The composite material (Ni-MOF/PANI) exhibits remarkable capacitive retention of 99.25 % even after undergoing 5000 cycles, as anticipated. In order to validate the aforementioned findings and determine the extent of the current contribution from capacitive and diffusive control, Dunn's model was employed. The data demonstrates the prevalence of diffusive-controlled (faradaic) current over capacitive current. The highest proportion of current resulting from diffusion is 96 %, achieved at a scan rate of 5 mV/s. The highest proportion of current resulting from capacitance is 24 %, achieved at a scan rate of 300 mV/s. At lower scan rates, the material exhibits a greater faradaic behaviour, whereas at higher scan rates, there is a progressive increase in non-faradaic processes. The insufficient time for diffusive process at higher scan rates is the cause. The Dunn's model with quadratic correction is also performed and comparative results were shown. Overall, the material exhibits more stability and dominance in the faradaic process, which paves the path for improved performance.

The interplay between optoelectronic and magnetic properties in Co-doped Cu2ZnSnS4 for next-generation solar cell devices

Abstract A search for next-generation solar cell devices to massively actualize renewable energy is being exponentially conducted. It includes the development of Cu2ZnSnS4 (CZTS)-based solar cells, which are known as cost-effective and highly stable solar cell devices. In this present research, we develop a CZTS solar cell by adding a magnetic degree of freedom using cobalt (Co) doping. We find that the Co doping can induce modulation of the crystalline structure and bandgap of CZTS, which further influences its photovoltaic performance. The increase in the grain size of the CZTS with the addition of Co doping could further induce the reduction of detrimental grain boundaries, which benefits the photovoltaic performance of CZTS-based solar cells. Co doping also generates magnetic behavior in CZTS, which supports its magnetically controlled optoelectronic properties and thus, in turn, enhances the photovoltaic performance. We believe that this study could open up opportunities to obtain next-generation solar cell devices with excellent performances by using magnetic-field induction.

Advanced Numerical Modeling of BaZrS3 Chalcogenide Perovskite Cells: Titanium Alloying and Back Surface Field Effects

Chalcogenide perovskites are emerging as superior alternatives to hybrid halide perovskites for photovoltaic applications due to their non-carcinogenic composition and enhanced environmental resilience, including superior resistance to moisture. This study focuses on the computational modeling of BaZrS3 (Barium Zirconium Sulfide) based solar cells, featuring a native bandgap of ∼1.71 eV. Through precise bandgap engineering via Ti alloying at the Zr site, the study aims to optimize the bandgap to the ideal range for photovoltaic efficiency. The device architecture is further refined by adjusting parameters such as layer thickness, doping densities, trap densities and metal contacts. The optimum device efficiencies at this stage were found to be 22.45 % for BaZrS3; 23.91 % for Ba(Zr0.99Ti0.01)S3; 26.64 % for Ba(Zr0.98Ti0.02)S3; and 27.74 % for Ba(Zr0.97Ti0.03)S3. Additionally, the incorporation of various back surface fields (BSFs) (CdTe, CIGS, CZTSe, Cu2Te, FeSi2, GeSe, PbS, µc-Si, SnTe, SnS, Sn2S3, and WSe2) is investigated to enhance photo-absorption. The findings indicate that a Ti alloying concentration of 3 % at the Zr site, coupled with a Cu2Te BSF, achieves the highest efficiency, approximately 30 %. These optimized structures present a robust framework for developing efficient, stable, and non-toxic photovoltaic devices utilizing chalcogenide perovskites.

Structural Stability of Mixed‐Halide Perovskite Nanocrystals in Energy Storage: The Role of Iodine Expulsion

AbstractIn the pursuit of efficient optoelectronics devices, hybrid lead halide perovskite quantum dots (PQDs) have emerged as highly promising semiconductor materials due to their intriguing properties. While these materials have been used in many applications, the fundamental understanding of their behavior remains relatively unexplored, especially for the mixed halide perovskite samples. To facilitate the advancement of PQD technologies for commercial applications, it is essential to gain insights into the role of ion migration. This study delves into the fundamental aspects of ion migration in halide perovskite nanocrystals. Porous electrodes for supercapacitor application were fabricated using CsPbBr3–xIx (x=0,1,2) nanocrystals prepared via the ligand‐assisted re‐precipitation (LARP) method. Three‐electrode electrochemical measurements and several other characterizations were conducted under dark conditions to evaluate device performance and elucidate the impact of mixed halides on device kinetics and stability. X‐ray photoelectron spectroscopy before and after the electrochemical measurement reveals intriguing findings. Notably, the analysis uncovered the phase segregation in the metal halide perovskite nanocrystals with particular emphasis on CsPbBr2I due to its distinctive mixed‐halide behavior. The specific capacitance increases with the increasing cycles. Interestingly, as the iodide content increases, there is no selective halide expulsion as the structure collapses rapidly.

Modeling and Optimization of Modified TiO2 with Aluminum and Magnesium as ETL in MAPbI3 Perovskite Solar Cells: SCAPS 1D Frameworks.

The perovskite device, incorporating a modified nanostructure of TiO2 as the electron transport layer, has been investigated to enhance its performance compared to the pure TiO2 device. Various materials undergo electrochemical doping or treatment on TiO2 to improve their photocatalytic application, thereby enhancing the current density, minimizing recombination, and improving device stability. In this study, a numerical SCAPS simulation was employed to validate experimental findings from the literature. According to the literature, this marks the first instance of doping Al3+ and Mg2+ on TiO2 due to their ionic radius comparable to that of Ti4+, at different doping concentrations. The device was modeled and simulated with the experimental parameters of bandgap, series, and shunt resistances for pure TiO2, aluminum-doped TiO2 (Al-TiO2), and magnesium-doped TiO2 (Mg-TiO2). From the validated results, the Al-TiO2 and Mg-TiO2-based devices' configurations with minimum percentage errors of 0.427 and 2.771%, respectively, were selected and simulated across nearly 90 (90) configurations to determine the optimum device model. Optimizing absorber thickness, bandgap, doping concentration, metal electrode, as well as series and shunt resistance resulted in enhanced device performance. According to the proposed model, Al-TiO2 and Mg-TiO2 configurations achieved higher power conversion efficiency values of 19.260 and 19.860%, respectively. This improvement is attributed to the reduction in recombination rates through the injection of a higher photocurrent density.

Hybrid Aromatic Fluoro Amine‐Modified SnO2 Electron Transport Layers in Perovskite Solar Cells for Enhanced Efficiency and Stability

SnO2 is a widely used electron‐transporting layer (ETL) in perovskite solar cells. Despite the high compatibility with the perovskite absorber layers, the presence of traps at the perovskite|SnO2 interface results in performance losses; hence, their modification to improve the performance and stability of perovskite solar cells (PSCs) is therefore important. Herein, the SnO2 ETL is enhanced by incorporating a bifunctional aromatic amino fluorine molecule into the SnO2 precursor solution. The fluorine molecule is found to partially substitute the Sn and alter the energy levels while the aniline group aids in regulating the nucleation/growth rate of the perovskite crystalline films. Herein, a hole transporting material‐free carbon‐based PSCs (CPSCs) is fabricated. It is found that perovskite absorber layers deposited on these modified SnO2 hybrid layers have higher optoelectronic quality, resulting in enhanced photovoltaic performance, device stability, and reduced hysteresis in CPSCs. Devices made with the modified hybrid SnO2 layers exhibit power conversion efficiencies of 15.6% significantly better than unmodified SnO2 with 13.5%. CPSCs with these modified SnO2 films also exhibit remarkable retention of 88.7% of their initial PCE for a shelf‐life period (ISOS‐D1I) exceeding 1200 h.

Solar-Hydrogen system of additional power supply and digital control system for on-board power supply system

Even for short space flights, such as manned flights to the Moon back in the 60s, it became extremely obvious that electric batteries are completely unsuitable because of their huge mass needed to store the required supply of onboard energy. Therefore, already in the 60s of the last century, the USA and the USSR took the path of using a hydrogen storage system using hydrogen fuel cells.Solar-hydrogen energy systems for spacecraft reliably provide energy for carrying out various kinds of unscheduled work on board and for eliminating emergency situations. Surplus energy is constantly accumulated on board in the form of the chemical energy of cryogenic hydrogen. The article presents too the result of the development of a solar-hydrogen power supply system for spacecraft, the onboard network of which provides slow and fast processes. This paper delves into designing digital control systems for power conditioning devices on the example of charging-discharging device based on a boost DC-DC converter. The device was implemented to condition a storage battery by properly charging and discharging it. A technique for constructing a small signal model of the converter has been developed. This involves constructing a block diagram using the discontinuous switching functions and analog models of electrical circuit components. The transfer functions of the analog controllers for the two-loop subordinate control system were derived. Then the procedure of a bilinear z-transform to the given transfer functions was applied. As a result, the discrete transfer functions of the digital controllers were obtained. Realization both analog and digital controllers in Matlab Simulink confirmed their identical behavior and stability within the power converter. Experimental studies of the static and dynamic waveforms of the digital control system showed controllability and stability of the charging-discharging device for the storage battery in typical operating modes. Thus, the method of synthesizing digital control systems for energy converters is proved valid and applicable for designing new power conditioning devices within modern power supplies.

High Thickness Tolerance in All-Polymer-Based Organic Photovoltaics Enables Efficient and Stable In-Door Operation.

Organic photovoltaics (OPVs) have great potential to drive low-power consumption electronic devices under indoor light due to their highly tunable optoelectronic properties. Thick devices (>300nm photo-active junctions) are desirable to maximize photocurrent and to manufacture large-scale modules via solution-processing. However, thick devices usually suffer from severe charge recombination, deteriorating device performances. Herein, the study demonstrates excellent thickness tolerance of all-polymer-based PVs for efficient and stable indoor applications. Under indoor light, device performance is less dependent on photoactive layer thickness, exhibiting the best maximum power output in thick devices (34.7 µW cm-2 in 320-475nm devices). Thick devices also exhibit much better photostability compared with thin devices. Such high thickness tolerance of all-polymer-based PV devices under indoor operation is attributed to strongly suppressed space-charge effects, leading to reduced bimolecular recombination losses in thick devices. The unbalanced charge carrier mobilities are identified as the main cause for significant space-charge effects, which is confirmed by drift-diffusion simulations. This work suggests that all-polymer-based PVs, even with unbalanced mobilities, are highly desirable for thick, efficient, and stable devices for indoor applications.

The Liquid Metal Age: A Transition From Hg to Ga.

This review offers an illuminating journey through the historical evolution and modern-day applications of liquid metals, presenting a comprehensive view of their significance in diverse fields. Tracing the trajectory from mercury applications to contemporary innovations, the paper explores their pivotal role in industry and research. The analysis spans electrical switches, mechanical applications, electrodes, chemical synthesis, energy storage, thermal transport, electronics, and biomedicine. Each section examines the intricacies of liquid metal integration, elucidating their contributions to technological advancements and societal progress. Moreover, the review critically appraises the challenges and prospects inherent in liquid metal applications, addressing issues of recycling, corrosion management, device stability, economic feasibility, translational hurdles, and market dynamics. By delving into these complexities, the paper advances scholarly understanding and offers actionable insights for researchers, engineers, and policymakers. It aims to catalyze innovation, foster interdisciplinary collaboration, and promote liquid metal-enabled solutions for societal needs. Through its comprehensive analysis and forward-looking perspective, this review serves as a guide for navigating the landscape of liquid metal applications, bridging historical legacies with contemporary challenges, and highlighting the transformative potential of liquid metals in shaping future technologies.

Controlling the temperature coefficient of dielectric constant of polyphenylene oxide-based composites

The temperature coefficient of dielectric constant (τε) is a crucial parameter for assessing the performance stability of microwave devices operating under varying temperature conditions. In this study, polyphenylene oxide (PPO) resin was utilized as the matrix and six types of ceramics with distinct temperature coefficients of dielectric constant were employed as fillers. Six PPO-based composites were fabricated through twin-screw extrusion combined with hot pressing route. The dielectric properties of the ceramics and their influence on the dielectric properties of the composites, particularly the τε, were systematically investigated. The results revealed that all six types of composites exhibited dense structures and uniform filler distribution, with a relative density exceeding 98.0 % and a water absorption below 0.1 %. The dielectric constant and its temperature coefficient of the fillers had a more pronounced effect on the dielectric properties of the composites, compared to dielectric loss. The dielectric constants of the six types of composites aligned well with the theoretical values predicted by the effective medium theory. Reaching up to 9.7 (at 10 GHz). The dielectric loss ranged from 1.0 × 10−3 to 3.0 × 10−3. Notably, the PPO/Mg0.95Ca0.05TiO3 composite substrate with a filler ratio of 40 vol% exhibited exceptional dielectric properties: εr = 6.8, tgδ = 1.4 × 10−3, τε = −8.6 ppm/°C, highlighting its significant advantages for communication applications under varying temperature conditions.

Linkage Regulation of Back‐To‐Back Connected Dimers as Guest Acceptors Enables Organic Solar Cells with Excellent Efficiency, Stability and Flexibility

AbstractHigh efficiency, stability, and flexibility are key prerequisites for the commercial applications of organic solar cells (OSCs). Herein, three back‐to‐back connected dimers (2Qx‐TT, 2Qx‐C3, 2Qx‐C6) are developed as the guest acceptors for OSCs with improved comprehensive performance. By regulating the linkage from rigid bithiophene to flexible alkyl chain, the back‐to‐back connected dimers display quite different molecular geometry and intermolecular interactions, consequently influencing their packing arrangement, film‐forming process, carrier mobilities, and the device efficiency, stability, and flexibility. By introducing these dimer acceptors as the guest into active layer, these dimers form alloy phases with the host acceptor, promoting film‐forming process and charge dynamics. All ternary devices exhibit improved PCEs of over 18% than the control binary device. Among them, 2Qx‐C3‐based ternary device obtains the best efficiency of as high as 19.03%. Moreover, thanks to the stronger entanglement favored by the dimers with flexible linkage, the PM6:BTP‐eC9:2Qx‐C3‐based device shows outstanding stability and flexibility. The flexible device displays an improved PCE of 16.09% with a crack‐onset strain of 15.0%, showing excellent mechanical robustness close to the all‐polymer devices. This work demonstrates the potential of the back‐to‐back connected dimer acceptors as the guest for highly efficient, stable and flexible OSCs.

An acoustic bellows-type round window transducer for middle-ear implants

BackgroundThis study describes the development of output devices for round window middle-ear. To overcome the problems of output devices that apply sound pressure directly to the round window, an acoustic bellows-type round window transducer was implemented by combining a small bellows, acoustic tube, and balanced armature driver. MethodsThe output characteristics of the proposed acoustic bellows-type round window transducer were confirmed through bench tests and distortion measurements. To compare the vibration transmission characteristics of the proposed transducer with those of sound pressure stimulation devices, an experiment was performed using four human temporal bones. FindingsThe average output magnitude of the acoustic bellows-type round window transducer was equivalent to sound pressure levels of 92, 96, and 108 dB for frequency ranges of <1, 1–2, and > 2 kHz, respectively. The results showed that the proposed transducer delivered vibration consistently without reducing the sound pressure level due to leakage, unlike the sound pressure stimulation device. InterpretationTherefore, the acoustic bellows-type round window transducer is a more stable and suitable output device for round window middle-ear implants than a sound pressure stimulation device. It is expected to overcome the limitations of sound pressure stimulation devices and to contribute to new technical solutions in the field of round window middle-ear implants development.

Optoelectronics of Lead‐Free Antimony‐ and Bismuth‐Based Metal Halides for Sensitive and Low‐Noise Photodetection

AbstractOrganic–inorganic hybrid halide perovskites have emerged as the most promising optoelectronic materials for next‐generation solution‐processed devices, primarily attributed to their distinctive properties such as cost‐effectiveness, facile fabrication process, high light absorption coefficient, tunable bandgap, and relatively high charge carrier mobility. Nevertheless, the presence of Pb elements is inevitable in most high‐performance perovskite optoelectronic devices, posing environmental pollution concerns and impeding their commercialization. In this study, two novel non‐toxic bismuth‐ and antimony‐based perovskite materials with environmentally conscious approaches are developed. Their structures and optoelectronic properties have been systematically characterized. Subsequently, photoconductive‐ and photodiode‐type photodetectors are designed and fabricated. Notably, the photodiode configuration exhibits exceptionally low dark current and noise, superior detection sensitivity, fast response speed, and good device stability. Owing to these superior performance metrics, the devices demonstrate great potential for real applications. Furthermore, this study furnishes a theoretical framework and design perspectives for the solution‐processed semiconductor materials.

Spin-Coated and Vacuum-Processed Hole-Extracting Self-Assembled Multilayers with H-Aggregation for High-Performance Inverted Perovskite Solar Cells.

We report a highly crystalline self-assembled multilayer (SAMUL) that is fundamentally different from the conventional monolayer or disordered bilayer used for hole-extraction in inverted perovskite solar cells (PSCs). The SAMUL can be easily formed on ITO substrate to establish better surface coverage to enhance the performance and stability of PSCs. A detailed structure-property-performance relationship of molecules used for SAMUL is established through a systematic study of their crystallinity, molecular packing, and hole-transporting properties. These SAMULs are rationally optimized by varying their molecular structures and deposition methods through thermal evaporation or spin-coating for fabricating PSCs. The CbzNaphPPA-based SAMUL was chosen for fabricating inverted PSCs due to it exhibiting the highest crystallinity and hole mobility which is derived from the ordered H-aggregation. This resulted in a remarkably high fill factor of 86.45 %, which enables a very impressive power conversion efficiency (PCE) of 26.07 % to be achieved along with excellent device stability (94 % of its initial PCE retained after continuous operation for 1200 h under 1-sun irradiation at maximum power point at 65 °C). Additionally, a record-high PCE of 23.50 % could be achieved by adopting a thermally evaporated SAMUL. This greatly simplifies and broadens the scope for SAM to be used for large-area devices on diverse substrates.

Non‐Ionic Perylene‐Diimide Polymer as Universal Cathode Interlayer for Conventional, Inverted, and Blade‐Coated Organic Solar Cells

AbstractAs a class of predominantly used cathode interlayers (CILs) in organic solar cells (OSCs), perylene‐diimide (PDI)‐based polymers exhibit intriguing characteristics of excellent charge transporting capacity and suitable energy levels. Despite that, PDI‐based CILs with satisfied film‐forming ability and adequate solvent resistance are rather rare, which not only limits the further advance of OSC performances but also hinders the practical use of PDI CILs. Herein, we designed and synthesized two non‐conjugated PDI polymers for achieving high power conversion efficiency (PCE) in diverse types of OSCs. The utilization of oligo (ethylene glycol) (OEG) linkage enhanced the n‐doping effect of PDI polymers, leading to an improved ability of the CIL to reduce work function and improve electron transporting capability. Moreover, the introduction of the non‐ionic OEG chain effectively improve the wetting property and solvent resistance of PDI polymers, so the PPDINN CIL can withstand diverse processing conditions in fabricating different OSCs, including conventional, inverted and blade‐coated devices. The binary OSC with conventional structure using PPDINN CIL showed a PCE of 18.6 %, along with an improved device stability. Besides, PPDINN is compatible with the large‐area blade‐coating technique, and a PCE of 16.6 % was achieved in the 1‐cm2 OSC where a blade‐coated PPDINN was used.

Non-Ionic Perylene-Diimide Polymer as Universal Cathode Interlayer for Conventional, Inverted, and Blade-Coated Organic Solar Cells.

As a class of predominantly used cathode interlayers (CILs) in organic solar cells (OSCs), perylene-diimide (PDI)-based polymers exhibit intriguing characteristics of excellent charge transporting capacity and suitable energy levels. Despite that, PDI-based CILs with satisfied film-forming ability and adequate solvent resistance are rather rare, which not only limits the further advance of OSC performances but also hinders the practical use of PDI CILs. Herein, we designed and synthesized two non-conjugated PDI polymers for achieving high power conversion efficiency (PCE) in diverse types of OSCs. The utilization of oligo (ethylene glycol) (OEG) linkage enhanced the n-doping effect of PDI polymers, leading to an improved ability of the CIL to reduce work function and improve electron transporting capability. Moreover, the introduction of the non-ionic OEG chain effectively improve the wetting property and solvent resistance of PDI polymers, so the PPDINN CIL can withstand diverse processing conditions in fabricating different OSCs, including conventional, inverted and blade-coated devices. The binary OSC with conventional structure using PPDINN CIL showed a PCE of 18.6 %, along with an improved device stability. Besides, PPDINN is compatible with the large-area blade-coating technique, and a PCE of 16.6 % was achieved in the 1-cm2 OSC where a blade-coated PPDINN was used.

Spin‐Coated and Vacuum‐Processed Hole‐Extracting Self‐Assembled Multilayers with H‐Aggregation for High‐Performance Inverted Perovskite Solar Cells

AbstractWe report a highly crystalline self‐assembled multilayer (SAMUL) that is fundamentally different from the conventional monolayer or disordered bilayer used for hole‐extraction in inverted perovskite solar cells (PSCs). The SAMUL can be easily formed on ITO substrate to establish better surface coverage to enhance the performance and stability of PSCs. A detailed structure‐property‐performance relationship of molecules used for SAMUL is established through a systematic study of their crystallinity, molecular packing, and hole‐transporting properties. These SAMULs are rationally optimized by varying their molecular structures and deposition methods through thermal evaporation or spin‐coating for fabricating PSCs. The CbzNaphPPA‐based SAMUL was chosen for fabricating inverted PSCs due to it exhibiting the highest crystallinity and hole mobility which is derived from the ordered H‐aggregation. This resulted in a remarkably high fill factor of 86.45 %, which enables a very impressive power conversion efficiency (PCE) of 26.07 % to be achieved along with excellent device stability (94 % of its initial PCE retained after continuous operation for 1200 h under 1‐sun irradiation at maximum power point at 65 °C). Additionally, a record‐high PCE of 23.50 % could be achieved by adopting a thermally evaporated SAMUL. This greatly simplifies and broadens the scope for SAM to be used for large‐area devices on diverse substrates.

Desıgn of quantum-dot semiconductor optical amplifiers wıth near-zero linewidth enhancement factor

The linewidth enhancement factor (LWEF) of a semiconductor optical amplifier (SOA) quantifies refractive index fluctuations in the gain medium, which induce phase distortion in the amplified optical signal. Optoelectronic systems employing SOAs with high LWEFs often exhibit poor device stability and beam coherence. Thus, designing SOAs with low LWEF is imperative. Recently, Quantum-Dot (QD) SOAs have emerged as a solution for LWEF suppression due to quantum-confinement effects enabling tunability of the QD carrier density and emission frequency. In this study, we aim to design a composite active region comprised of a host medium and the embodied QDs, to explore the corresponding LWEF variation and propose the ultimate design strategy to achieve near-zero LWEF in QD SOAs for enhancing device stability and beam coherence. Our approach entails modeling the refractive index of the composite active region using effective medium approximation via Maxwell–Garnett mixing formulation. We then extensively tune key SOA parameters, including QD carrier density, QD emission frequency, and the collision-time constant of the carriers to uncover the optimal configuration for minimizing the LWEF. Based on empirical values, we have developed and validated a simple yet effective algorithm that precisely simulates LWEF behavior in response to changes in key QD SOA parameters. This approach offers a straightforward model for estimating LWEF variation, and its corresponding minimization in QD SOAs without requiring complex experimental measurement techniques.

Nanoparticle-Enabled Zn-0.1Mg Alloy with Long-Term Stability, Refined Degradation, and Favorable Biocompatibility for Biodegradable Implant Devices.

Zinc-based alloys, specifically Zn-Mg, have garnered considerable attention as promising materials for biodegradable implants due to their favorable mechanical strength, appropriate corrosion rate, and biocompatibility. Nevertheless, the alloy's lack of mechanical stability and integrity, resulting from ductility loss induced by age hardening at room temperature, hampers its practical bioapplication. In this study, ceramic nanoparticles have been successfully incorporated into the Zn-Mg alloy system, leading to a significant improvement in long-term stability as well as mechanical strength and ductility. In addition, this study represents the first investigation of Zn-based nanocomposites both in vitro and in vivo to comprehend the influence of nanoparticles on the degradation behavior and biocompatibility of the Zn system. The findings indicate that the incorporation of WC nanoparticles effectively refines and stabilizes the degradation behavior of Zn-Mg without negatively impacting the cytocompatibility of the alloy. The subcutaneous implantation and femoral implantation further prove the benefits of nanoparticle incorporation and found no negative effects. Collectively, Zn-Mg-WC nanocomposites yield great potential for implant usage.