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In high energy density physics, the demand for precise detection of nanosecond-level fast physical processes is high. Ga:ZnO (GZO), GaN, and other fast scintillators are widely used in pulsed signal detection. However, many of them, especially wide-bandgap materials, still face issues of low luminous intensity and significant self-absorption. Therefore, an enhanced method was proposed to tune the wavelength of materials via coating perovskite quantum dot (QD) films. Three-layer samples based on GZO were primarily investigated and characterized. Radioluminescence (RL) spectra from each face of the samples, as well as their decay times, were obtained. Lower temperatures further enhanced the luminous intensity of the samples. Its overall luminous intensity increased by 2.7 times at 60 K compared to room temperature. The changes in the RL processes caused by perovskite QD and low temperatures were discussed using the light tuning and transporting model. In addition, an experiment under a pico-second electron beam was conducted to verify their pulse response and decay time. Accordingly, the samples were successfully applied in beam state monitoring of nanosecond pulsed proton beams, which indicates that GZO wafer coating with perovskite QD films has broad application prospects in pulsed radiation detection.

The nonlinear compression of narrowband (Δν ≈ 0.2 cm[sup.−1]) 20 ns KrF laser pulses in SF[sub.6] at 10 atm and in CH[sub.4] at 50 atm pressure was studied. Both SBS and SRS optically phase-conjugated backward-reflected radiation was registered with an energy reflectivity of 10–14% in SF[sub.6] and CH[sub.4]. In SF[sub.6], the SBS pulses gradually shortened from 10 ns to 2–3 ns with a decrease in pumping to the SBS threshold of ~10 mJ, while the SRS pulse had the shortest length of 30–60 ps for the maximal pumping of 120 mJ and broadened near the SRS threshold of ~30 mJ. For the SRS pulse energy, the ~2 mJ peak power 5 × 10[sup.7] W was tenfold higher than the pump power. The theoretical model predicted a soliton-like SRS pulse compression to a temporal length of the order of the vibrational relaxation time. There was no pulse compression of backward SBS and SRS radiation in CH[sub.4], while, in the forward direction, SRS pulses shortened to 3–4 ns at reduced pumping.

Focusing laser light onto a very small target can produce the conditions for laboratory-scale nuclear fusion of hydrogen isotopes. The lack of accurate predictive models, which are essential for the design of high-performance laser-fusion experiments, is a major obstacle to achieving thermonuclear ignition. Here we report a statistical approach that was used to design and quantitatively predict the results of implosions of solid deuterium–tritium targets carried out with the 30-kilojoule OMEGA laser system, leading to tripling of the fusion yield to its highest value so far for direct-drive laser fusion. When scaled to the laser energies of the National Ignition Facility (1.9 megajoules), these targets are predicted to produce a fusion energy output of about 500 kilojoules—several times larger than the fusion yields currently achieved at that facility. This approach could guide the exploration of the vast parameter space of thermonuclear ignition conditions and enhance our understanding of laser-fusion physics. A statistical approach to designing and predicting the fusion yield of cryogenic deuterium–tritium implosions leads to tripled yield in direct-drive laser fusion of deuterium–tritium layered targets.

A review of theoretical and experimental studies in the field of compression and heating of a plasma target in an external magnetic field, which has recently been called magneto-inertial fusion (MIF), has been carried out. MIF is a concept of magnetically driven inertial fusion that involves the magnetization of fuel, laser pre-heating, and magnetic implosion to create fusion conditions. An analysis of the current state of work on the implosion of magnetized targets and the effect of an external magnetic field on the main plasma parameters and system characteristics is presented. Questions regarding the numerical simulation of experiments on the magnetic-inertial confinement of plasma are touched upon. Particular attention is paid to two promising areas of MIF—with plasma jets and with a laser driver (laser beams).

The application range of fused silica optical components can be expanded and the cost of fused silica components can be reduced by depositing the same material film on fused silica substrate. However, due to the different manufacturing process, the performance of ALD SiO[sub.2] film is lower than that of fused silica substrate, which also limits the use of this process. In this paper, ALD SiO[sub.2] film with different thicknesses were deposited, and then the structure and properties were tested. Finally, the ALD SiO[sub.2] film was treated via the annealing process. Transmission electron microscopy (TEM) showed that the ALD SiO[sub.2] film had good compactness and substrate adhesion. The Raman spectra showed that the ALD SiO[sub.2] film and substrate had the same structure, with only slight differences. The XRD pattern showed that ALD-fused silica did not crystallize before or after annealing. The infrared spectra showed that there was an obvious Si-OH defect in the ALD SiO[sub.2] film. The laser damage showed that the ALD SiO[sub.2] film had a much lower damage threshold than the fused silica substrate. The nanoindentation showed that the mechanical properties of the ALD SiO[sub.2] film were much lower than those of the fused silica substrate. After a low-temperature annealing treatment, the ALD SiO[sub.2] film Si-OH defect was reduced, the ALD SiO[sub.2] film four-member ring content was increased, the elastic modulus of the ALD SiO[sub.2] film was increased from 45.025 GPa to 68.025 GPa, the hardness was increased from 5.240 GPa to 9.528 GPa, and the ALD SiO[sub.2] film damage threshold was decreased from 5.5 J/cm[sup.2] to 1.3 J/cm[sup.2].

HB11 Energy’s mission is to realize large-scale electricity generation from the fusion of hydrogen with boron-11 (the HB11, or “proton-boron”, reaction) without the environmental problems normally associated with nuclear energy. A non-thermal approach is taken in the initiation of the reaction using high-peak-power lasers, which was the pursuit of HB11 Energy founder Prof. Heinrich Hora’s career as a theoretical physicist. In the 1980s, the invention of Chirped Pulse Amplification (CPA) of laser pulses by Donna Strickland and Gerard Mourou (Nobel Prize 2018) enabled the possibility of experimentally validating the earlier theoretical predictions. Several experimental demonstrations of the HB11 reaction using CPA lasers inspired the establishment of HB11 Energy and with it, the possibility of realizing an aneutronic nuclear energy source with easily accessible and safe fuel resources that could last thousands of years. Like all quests for fusion energy, there are significant scientific challenges remaining. HB11 Energy Holdings Pty Ltd, an Australian company, was established as the best vehicle to co-ordinate a global collaborative research effort to address these challenges and build capacity to host large-scale public private partnerships, such as those now recommended by the US National Academies of Science, Engineering and Medicine (NASEM) (US National Academies of Sciences, Engineering and Medicine in Bringing Fusion to the U.S. Grid,: National Academies Press, Washington, D.C, 2021). If net-energy-gain can be achieved through HB11 Energy’s concepts, there are many engineering benefits over traditional DT fusion that will see a dramatically simpler and safer reactor being produced. A technoeconomic assessment of such a reactor is also discussed which presents many engineering challenges that will need to be met before commercial HB11 fusion can be deployed on a large-scale.

Fused silica has become the preferred optical material in the field of inertial confinement fusion (ICF) due to its excellent performance; however, these costly optical elements are vulnerable, and their manufacture is time-consuming. Therefore, the restoration of laser-induced damage for these optical elements is of great value. To restrain the post-restoration raised rim problem in the CO[sub.2] laser repair process to improve the restoration quality, the separate influences of key parameters of laser power, irradiation duration, and laser beam diameter on post-restoration pit morphology are compared in combined simulation and experimental studies. An optimized, patterned CO2 laser strategy is proposed and verified; the results indicate that, with the strategy, the rim height decreases from 2.6 μm to 1.52 μm, and maximal photo thermal absorption is decreased from 784.2 PPM to 209.43 PPM.

Focused Energy is a new startup company with the goal of developing laser-driven inertial fusion energy for electrical power production. The company combines the results from decades of fundamental research in inertial confinement fusion at universities and national laboratories with the flexibility and the speed of a startup company. Focused Energy has chosen the direct-drive, proton fast ignition approach to reach ignition, burn and high gain as the most promising approach. Located in Austin/US and Darmstadt/Germany, supported by the science community and private investment Focused Energy is paving the way to inertial fusion energy combining the best skill set and state-of-the-art technology from both sides of the Atlantic Ocean. In this paper we discuss the details and reasoning for the approach and the technical directions we have chosen. We will outline our roadmap for getting to a fusion pilot plant in the mid to late 2030s.

Nuclear fusion is understood as an energy reaction that does not emit greenhouse gases, and it has been considered as a long-term source of low-carbon electricity that is favourable to curtail rapid climate change. Fusion offers a pathway to resolve energy security and the unequal distribution of energy resources since seawater is its ultimate fuel source and a few grams of fuel can generate mega kilowatts of power. The development and testing of new materials and technologies are unceasing to achieve the net fusion energy through national and international collaboration as well as private partnerships. The ever-growing number of research works report various designs and magnet-based fusion devices, such as stellarators, lasers, and tokamaks. This article provides an overview on the utilization of nuclear energy as a clean energy source, as well as the strategies and progress towards establishing successful commercial fusion energy to the grid and transition to a reliable clean energy source. The overview focuses on the fusion nuclear development in five major countries, UK, US, China, Japan, and Russia. Identified technical and financial challenges are also described at the end of this article. The International Thermonuclear Experimental Reactor (ITER) has been an international reference program for fusion energy development and most developed countries with nuclear development capacity are aiming to complete their in-house fusion energy facilities in parallel to ITER. Many fusion programs are finishing the conceptual design and shifting into the phase of engineering design for the planned DEMO fusion facilities. The significant challenges were identified from the perspective of device efficiency and robustness, sustainable funding, and facility maintenance and safety, which must be addressed diligently to realize fusion energy as alternative clean energy that mitigates climate change and supports the goals of energy security.

Intentionally adding select ions such as Al[sup.3+] could be helpful in controlling the crystal habit of KDP crystal for high yield of optics. The study of how Al[sup.3+] ions affect crystal quality can provide a basis for selecting an appropriate doping level without negatively affecting the optical properties of crystals. Here, the influence of Al[sup.3+] ions on the crystal structure and properties of KDP crystals have been investigated by using first-principles calculations. Theoretical calculations show that Al[sup.3+] ions mainly replace K sites in KDP crystals and could complex with intrinsic V[sub.H] [sup.−] point defects to form Al[sub.K] [sup.2+] + 2V[sub.H] [sup.−] cluster defects. The linear absorption spectra indicate that the presence of Al[sup.3+] ions has minimal impact on the linear absorption of KDP crystals, aligning well with the experimental findings. And Al[sup.3+] ions could cause a slight shortening of the band gap of KDP crystals. However, these ions could bring significant deformations of O-H bonds. As the concentration of Al[sup.3+] ions increase, more O-H bonds linking to PO[sub.4] groups are distorted in KDP crystals. As a result, the structural instability could be fast enhanced with increasing the defect concentration. Therefore, high concentrations of Al[sup.3+] ions could cause the instability of the crystal structure, which finally affects the laser-induced damage resistance of the KDP crystals. This manuscript contributes to a more comprehensive understanding of the physical mechanisms by which different impurity ions affect the optical properties of KDP crystals.