This work investigates the radiation resilience of mixed-cation mixed-halide (FA0.65MA0.35)0.92Pb(I0.85Br0.14Cl0.01)3 perovskite thin films under 15.5 MeV proton irradiation, focusing on the protective role of a methylammonium chloride (MACl) processing additive. Three distinct sample conditions were systematically compared, an unirradiated pristine film without MACl, an irradiated control film without MACl and an irradiated optimized film with MACl․ Scanning electron microscopy (SEM) analysis revealed that introducing MACl drastically alters crystallization kinetics, expanding the average grain size from 150-200 nm to 500-600 nm, thereby reducing vulnerable grain boundary density. Following proton bombardment at a cumulative fluence of 5 x 1015 protons⋅cm-2, the control film exhibited severe morphological micro-cracks along grain junctions, surface decomposition, and a dramatic quenching of its photoluminescence (PL) intensity down to 20% of its initial value, alongside a suppressed optical absorbance edge. These changes signify the massive formation of deep-level defect centers via atomic displacement. Conversely, the irradiated MACl optimized film demonstrated superior radiation hardness, maintaining its compact morphological integrity without cracking, preserving its absorption profile, and retaining 70% of its initial PL intensity. This enhanced stability is attributed to the minimization of boundary-mediated defect propagation paths and effective trap passivation by localized chloride ions. Type:
An integral representation for interacting particles and for the description of systems of particles in nonequilibrium is used to represent the total radiation energy density of the universe ρR by means of the integral representation resulting in a value for the effective number Neff of cosmological neutrinos, Neff = 87(114)4/3 =4.4032···.
This study investigates a method for the passive control of the dynamics of a pulsed-periodic electric discharge and transitions between plasma modes (glow discharge vs. arc) by selecting the parameters of an external relaxation RC circuit. A physical model of the self-oscillatory process is proposed, accounting for the stages of storage capacitor charging, pulsed breakdown, and automatic arc extinction when the discharge current drops below the critical current required to sustain the cathode spot (Id < Icrit). It has been demonstrated that matching the charging and ballast resistances, capacitor capacitance, and supply voltage makes it possible to achieve a stable pulsed mode with adjustable frequency without the use of power semiconductor switches. The implemented mode ensures thermal self-limitation of the cathode and the virtual absence of large droplets.
This study demonstrates a significant performance enhancement in all-inorganic green perovskite light-emitting diodes (PeLEDs) by utilizing a p–i–n architecture (ITO/PEDOT:PSS/CsPbBr3/TPBi/LiF/Al). The research focuses on the synergistic effects of incorporating Strontium Chloride (SrCl2) and Lithium Bromide (LiBr) as dual-additives into the CsPbBr3 emissive layer. The introduction of these additives effectively passivates surface defects and halide vacancies, which reduces non-radiative energy losses and improves charge carrier transport within the device structure. Experimental results show that the optimized devices achieve a peak external quantum efficiency (EQE) of 2.95%, representing a nearly 50% improvement over the 1.9% efficiency of the control samples. Furthermore, the additives ensure a high-purity green emission at 512 nm with improved color saturation. These findings provide a clear and reproducible pathway toward developing high-efficiency, stable, and cost-effective all-inorganic green LEDs for next-generation optoelectronic applications.
An earlier work that replaced the de Sitter-Schwarzschild metric for a cosmological constant Lambda <=0 by an effective anti-de Sitter black hole analytic at Lambda = 0 is here extended to the horizon structure through its three possible roots. We replace the de Sitter-Schwarzschild metric for all possible values of Lambda and the Schwarzschild radius R for the three possible available roots by either a Schwarzschild black hole whose radius depends on both R and Lambda or a de Sitter space whose cosmological constant depends on both R and Lambda.
