High Power Laser Science and Engineering
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High Power Laser Science and Engineering 第5卷 第1期

Author Affiliations
Abstract
1 Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 University of Chinese Academy of Sciences, Beijing 100049, China
3 Laser Fusion Research Center, Chinese Academy of Engineering Physics, Mianyang, Sichuan 621900, China
This work presents a brief introduction on three kinds of newly developed $\text{Nd}^{3+}$-doped laser glasses in Shanghai Institute of Optics and Fine Mechanics (SIOM), China. Two $\text{Nd}^{3+}$-doped phosphate glasses with lower thermal expansion coefficient and thermal shock resistance 4 times higher than that of N31 glass are developed for laser processing. Nd:Silicate and Nd:Aluminate glasses with peak emission wavelength at 1061 and 1065 nm, effective emission bandwidth of 34 and 50 nm, respectively, are developed for Exawatt-class laser system application. Fluorophosphate glasses with low nonlinear refractive index ($n_{2}=0.6{-}0.86$) and long fluorescence lifetime ($430{-}510~\unicode[STIX]{x03BC}\text{s}$) are investigated for the purpose of decreasing B integral in high-power laser system. The properties of all these glasses are presented and compared with those of commercial neodymium laser glasses.
aluminate glass fluorophosphate glass high-power laser neodymium laser glass phosphate glass silicate glass 
High Power Laser Science and Engineering
2017, 5(1): 010000e1
Author Affiliations
Abstract
1 GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
2 Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Caparica, Portugal
3 Department of Physics & Astronomy, College of Science, King Saud University, Riyadh, Saudi Arabia
The Laboratory for Intense Lasers (L2I) is a research centre in optics and lasers dedicated to experimental research in high intensity laser science and technology and laser plasma interaction. Currently the laboratory is undergoing an upgrade with the goal of increasing the versatility of the laser systems available to the users, as well as increasing the pulse repetition rate. In this paper we review the current status of the laser research and development programme of this facility, namely the upgraded capability and the recent progress towards the installation of an ultrashort, diode-pumped OPCPA laser system.
diode-pumped solid-state laser and applications femtosecond laser and applications frequency conversion laser amplifiers nonlinear optics 
High Power Laser Science and Engineering
2017, 5(1): 010000e2
Author Affiliations
Abstract
1 Grupo de Investigación en Aplicaciones del Láser y Fotónica, Departamento de Física Aplicada, University of Salamanca, E-37008, Salamanca, Spain
2 Argonne National Laboratory, Argonne, IL 60439, USA
Optical vortices are structures of the electromagnetic field with a spiral phase ramp about a point-phase singularity, carrying orbital angular momentum (OAM). Recently, OAM has been imprinted to short-wavelength radiation through high-order harmonic generation (HHG), leading to the emission of attosecond twisted beams in the extreme-ultraviolet (XUV) regime. We explore the details of the mapping of the driving vortex to its harmonic spectrum. In particular, we show that the geometry of the harmonic vortices is convoluted, arising from the superposition of the contribution from the short and long quantum paths responsible of HHG. Finally, we show how to take advantage of transverse phase-matching to select twisted attosecond beams with different spatiotemporal properties.
attosecond science extreme-ultraviolet vortices high harmonic generation orbital angular momentum twisted beams vortex beams 
High Power Laser Science and Engineering
2017, 5(1): 010000e3
Author Affiliations
Abstract
1 Centre for Plasma Physics, School of Mathematics and Physics, Queen’s University of Belfast, BT7 1NN, UK
2 Institut für Laser-und Plasmaphysik, Heinrich-Heine-Universität, Düsseldorf, Germany
The ultrafast charge dynamics following the interaction of an ultra-intense laser pulse with a foil target leads to the launch of an ultra-short, intense electromagnetic (EM) pulse along a wire connected to the target. Due to the strong electric field (of the order of $\text{GV m}^{-1}$) associated to such laser-driven EM pulses, these can be exploited in a travelling-wave helical geometry for controlling and optimizing the parameters of laser accelerated proton beams. The propagation of the EM pulse along a helical path was studied by employing a proton probing technique. The pulse-carrying coil was probed along two orthogonal directions, transverse and parallel to the coil axis. The temporal profile of the pulse obtained from the transverse probing of the coil is in agreement with the previous measurements obtained in a planar geometry. The data obtained from the longitudinal probing of the coil shows a clear evidence of an energy dependent reduction of the proton beam divergence, which underpins the mechanism behind selective guiding of laser-driven ions by the helical coil targets.
acceleration EM pulse ion laser proton proton probing 
High Power Laser Science and Engineering
2017, 5(1): 010000e4
Author Affiliations
Abstract
Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900, China
As the basic conditions for laser inertial confinement fusion (ICF) research, the targets are required to be well specified and elaborately fabricated. Because of the characteristics of the targets, the research and fabrication process is a systematically tough task, which needs fundamental and deep insights into film deposition, mechanical machining, precise measurement and assembly, etc. As a result, knowledge of material science, physics, mechanical as well as electronics is a necessity for target researchers. In this paper, we give introductions to the state of art on target fabrication for ICF research at Research Center of Laser Fusion (RCLF) in China.
development ICF target fabrication 
High Power Laser Science and Engineering
2017, 5(1): 010000e5
Author Affiliations
Abstract
1 Rochester Institute of Technology, 78 Lomb Memorial Drive, Rochester, NY 14623-5604, USA
2 Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, NY 14623-1299, USA
3 General Atomics, San Diego, CA 92186, USA
4 Lawrence Livermore National Laboratory, Livermore, CA 94550, USA
A unique approach for permeation filling of nonpermeable inertial confinement fusion target capsules with deuterium–tritium (DT) is presented. This process uses a permeable capsule coupled into the final target capsule with a 0.03-mm-diameter fill tube. Leak free permeation filling of glow-discharge polymerization (GDP) targets using this method have been successfully demonstrated, as well as ice layering of the target, yielding an inner ice surface roughness of 1-$\unicode[STIX]{x03BC}$m rms (root mean square). Finally, the measured DT ice-thickness profile for this experiment was used to validate a thermal model’s prediction of the same thickness profile.
fill-tube inertial confinement fusion permeation fill target capsule 
High Power Laser Science and Engineering
2017, 5(1): 010000e6