Publications by authors named "A L Rigatti"
Article Synopsis
- High-energy laser facilities need specialized multilayer coatings on large surfaces, requiring strict control over deposition parameters to achieve desired optical and mechanical qualities.
- The study expands the understanding of how relative humidity affects these coatings, causing shifts in their optical spectra, which are usually limited to a narrow wavelength range.
- Validation of the spectral shift method involved comparing the effects of humidity on single layers with simulated changes due to thickness or refractive index, revealing that humidity primarily influences the refractive index, with SiO being more responsive than HfO.
Monolayers containing subnanometer striations of silica and hafnia to form composite materials at varying ratios are explored as a method to develop high-index dielectric layers with increased laser-induced-damage thresholds (LIDTs). These layers can then be used in multilayer dielectric coatings for short-pulse, high-peak-power laser applications, particularly in regions of the highest electric-field intensity. Fabrication is achieved by means of exposure to two different evaporant vapor plumes, where local exposure to each plume is controlled via shielding to prevent simultaneous exposure.
View Article and Find Full Text PDFAchievement of Target Gain Larger than Unity in an Inertial Fusion Experiment.
Phys Rev Lett
February 2024
Article Synopsis
- * This experiment produced 2.05 MJ of laser energy, resulting in 3.1 MJ of total fusion yield, which exceeds the Lawson criterion for ignition, demonstrating a key milestone in fusion research.
- * The report details the advancements in target design, laser technology, and experimental methods that contributed to this historic achievement, validating over five decades of research in laboratory fusion.
Contamination of pulse compression gratings during the manufacturing process is known to give rise to reduced laser damage performance and represents an issue that has not yet been adequately resolved. The present work demonstrates that the currently used etching methods introduce carbon contamination inside the etched region extending to a 50- to 80-nm layer below the surface. This study was executed using custom samples prepared in both, a laboratory setting and by established commercial vendors, showing results that are very similar.
View Article and Find Full Text PDFArticle Synopsis
- * In inertially confined fusion, ignition allows the fusion process to spread into surrounding fuel, potentially leading to higher energy output.
- * Recent experiments at the National Ignition Facility achieved capsule gains of 5.8 and approached ignition, even though "scientific breakeven" has not yet been fully realized.