Laser Damage最新文献

Optical damage considerations in the design of the matter in extreme condition upgrade (MEC-U) laser systems 极端条件下物质升级（MEC-U）激光系统设计中的光学损伤考虑因素

Laser Damage Pub Date : 2023-11-24 DOI: 10.1117/12.2685218

Steven T. Yang, Michael R. Greenberg, Eric Cunningham, Mikael D. Martinez, R. Negres, T. Spinka, Stavros G. Demos, Amy L. Rigatti

引用次数: 0

Monte Carlo analysis of ISO and raster scan laser damage protocols: part 2 ISO 和光栅扫描激光损伤协议的蒙特卡罗分析：第 2 部分

Laser Damage Pub Date : 2023-11-24 DOI: 10.1117/12.2684458

Christopher J. Stolz

引用次数: 0

THGs for NIF operations (>2 MJ NIF operations) 用于 NIF 运行的 THGs（>2 MJ NIF 运行）

Laser Damage Pub Date : 2023-11-24 DOI: 10.1117/12.2684120

K. Schaffers, Christopher J. Stolz, John J. Adams, R. Negres, M. Monticelli

{"title":"THGs for NIF operations (>2 MJ NIF operations)","authors":"K. Schaffers, Christopher J. Stolz, John J. Adams, R. Negres, M. Monticelli","doi":"10.1117/12.2684120","DOIUrl":"https://doi.org/10.1117/12.2684120","url":null,"abstract":"Lawrence Livermore National Security’s (LLNS) National Ignition Facility (NIF) requires over 600 large crystals of KH2PO4 (KDP) and KH0.6D1.4PO4 (DKDP) for use in polarization rotation and frequency conversion assemblies. There are near term plans to increase the energy on NIF to 2.2 MJ and up to 3 MJ in future years. Managing optics’ damage is one critical aspect of achieving these aggressive goals. Frequency conversion crystals are being examined for readiness to meet the goals for higher energy operations. All aspects of the crystal fabrication process are being studied including growth, processing, laser conditioning, and mitigation to strengthen the crystals against damage. THG crystals have an approximately 10× lower exchange rate than fused silica optics, so unlike NIF fused silica optics which are micromachined to mitigate surface laser damage between recycle loops, THG crystals are refinished to remove surface laser damage. Given the long time to grow NIF size DKDP crystals (3 years) and the impact of THG thickness on frequency conversion, a good understanding of the evolution of the inventory is necessary. The number of damage sites that require laser blocking dictates the exchange rate of THG crystals. Understanding the difference between bulk and surface damage, is important to limit the number of blocked sites. Also, in preparation for higher power operations on NIF, the current KDP polarization rotators on half of the NIF beams are being exchanged with DKDP due to an ~5% reduction in absorption at 1053 nm thus reducing beam contrast in the NIF amplifiers.","PeriodicalId":202227,"journal":{"name":"Laser Damage","volume":"28 1","pages":"1272603 - 1272603-9"},"PeriodicalIF":0.0,"publicationDate":"2023-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139241308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Bandgap energy of quantizing nanolaminates and its relation to the laser-induced damage threshold in the ultraviolet 量化纳米层压板的带隙能及其与紫外线激光诱导损伤阈值的关系

Laser Damage Pub Date : 2023-11-24 DOI: 10.1117/12.2685250

S. Paschel, M. Steinecke, T. Kellermann, K. Kiedrowski, A. Melninkaitis, M. Jupé, Andreas Wienke, Detlev Ristau

引用次数: 0

Shockwave and crack monitoring following nonlinear absorption with picosecond time-resolved microscopic imaging 利用皮秒时间分辨显微成像技术监测非线性吸收后的冲击波和裂纹

Laser Damage Pub Date : 2023-11-24 DOI: 10.1117/12.2685245

Matthew R. Ross, Jue Wang

引用次数: 0

An overview on laser damage performance of current AR-coated windows at 343 nm and ultrashort pulses 当前 AR 涂层窗口在 343 纳米和超短脉冲下的激光损伤性能概览

Laser Damage Pub Date : 2023-11-24 DOI: 10.1117/12.2686252

J. Vanda, Martin Mydlář, Priyadarshani Narayanasamy, Hana Turcicova, Radek Poboril, J. Brajer, T. Mocek

引用次数: 0

Determining the bandgap dependence of nonlinear absorption and laser induced damage threshold through numerical simulation and experiment 通过数值模拟和实验确定非线性吸收和激光诱导损伤阈值的带隙依赖性

Laser Damage Pub Date : 2023-11-24 DOI: 10.1117/12.2685160

Joshua McCauley, Xiaochuan Ji, M. Jupé, Jinlong Zhang, Andreas Wienke, Detlev Ristau

{"title":"Determining the bandgap dependence of nonlinear absorption and laser induced damage threshold through numerical simulation and experiment","authors":"Joshua McCauley, Xiaochuan Ji, M. Jupé, Jinlong Zhang, Andreas Wienke, Detlev Ristau","doi":"10.1117/12.2685160","DOIUrl":"https://doi.org/10.1117/12.2685160","url":null,"abstract":"Nonlinear absorption is mainly governed by mechanisms involving excitation processes of electrons. Typically, two phenomena are considered when discussing nonlinear absorption; the multiphoton absorption where multiple photons interact directly with a single electron, and tunnel ionization, where the high electric field results in a shifting of the bandgap allowing an electron to tunnel into the conduction band. Electrons in the conduction band can be accelerated through the absorption of further photons until they obtain enough energy to excite further electrons to the conduction band, leading to runaway absorption and finally damage of the sample. By laser calorimetric measurement of the nonlinear absorption, it is expected that the laser damage threshold can be predicted without damaging the optic. Before accurate predictions can be made, the process must be thoroughly characterized and understood. The nonlinear behavior of the absorption was demonstrated with potential increases in absorption of an order of magnitude. Initial results show a noticeable impact of contaminants, though a nonlinear response is still observed.","PeriodicalId":202227,"journal":{"name":"Laser Damage","volume":"76 10","pages":"127260J - 127260J-6"},"PeriodicalIF":0.0,"publicationDate":"2023-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139242016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Broadband, 920-nm mirror thin film damage competition 宽带、920 纳米镜面薄膜损坏竞争

Laser Damage Pub Date : 2023-11-24 DOI: 10.1117/12.2685127

R. Negres, Kyle P. Kafka, Christopher Smith, Marek Stehlik, Sarah Olandt, Stavros G. Demos, Amy L. Rigatti

{"title":"Broadband, 920-nm mirror thin film damage competition","authors":"R. Negres, Kyle P. Kafka, Christopher Smith, Marek Stehlik, Sarah Olandt, Stavros G. Demos, Amy L. Rigatti","doi":"10.1117/12.2685127","DOIUrl":"https://doi.org/10.1117/12.2685127","url":null,"abstract":"This year’s competition proposed to survey the state-of-the-art broadband, near-IR multilayer dielectric (MLD) mirrors designed for ultra-short, pulsed laser applications. The requirements for the coatings were a minimum reflection of 99.5% at 45-degree incidence angle for S-polarization from 830 nm to 1010 nm and group delay dispersion (GDD) < ± 50 fs2. The participants in this effort selected the coating materials, coating design, and deposition method. Samples were damage tested at a single testing facility to enable direct comparison among the participants using a 25 ± 5 fs OPCPA laser system operating at 5 Hz. A double blind test assured sample and submitter anonymity. The damage performance results, sample rankings, details of the deposition processes, coating materials and substrate cleaning methods are shared here. We found that multilayer coatings using tantala and/or hafnia as high index materials were top performers within several coating deposition groups. Specifically, dense coatings by ion-beam sputtering (IBS), magnetron sputtering (MS), and electron-beam ion assisted deposition (e-beam IAD) exhibited highest damage initiation onset (LIDT) while e-beam coatings were low performers. In addition, damage growth onset (LDGT) was also examined and the results are reported here for all samples as this performance metric plays an important role in establishing the safe operational conditions for larger aperture, ultrashort pulsed lasers. Lastly, not all coating samples in the survey met the GDD requirements stated above and associated measurements are discussed in the context of the present and past competitions focused on similar broadband, near-IR MLD coatings.","PeriodicalId":202227,"journal":{"name":"Laser Damage","volume":"130 4","pages":"1272606 - 1272606-12"},"PeriodicalIF":0.0,"publicationDate":"2023-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139239155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fusion enabling laser-induced damage reduction, management, and repair strategies at the National Ignition Facility 国家点火装置的聚变激光诱导损伤减少、管理和修复战略

Laser Damage Pub Date : 2023-11-24 DOI: 10.1117/12.2688417

C. W. Carr

引用次数: 0

Exploring self-healing liquid metal mirrors for high-power laser applications 探索用于高功率激光应用的自修复液态金属反射镜

Laser Damage Pub Date : 2023-11-24 DOI: 10.1117/12.2685176

Gregory S. Demos, Brittany N. Hoffman, J. Lambropoulos, Marcela Mireles

引用次数: 0