Cyclops was a high-power laser built at the Lawrence Livermore National Laboratory (LLNL) in 1975. It was the second laser constructed in the lab's Laser program, which aimed to study inertial confinement fusion (ICF).[1]
The Cyclops was a single-beam Neodymium glass (Nd:glass) laser. The Janus laser, a two-beam version of it, was also completed in 1975. The main scientific aims of its construction were for the study of nonlinear focusing effects in high power laser beams, novel amplification techniques (disks of Nd:glass at the brewster angle), spatial filtering techniques which would be used on subsequent higher powered lasers such as the Argus and Shiva lasers and for inertial confinement fusion (ICF) research.
Background
Even the earliest ICF laser experiments demonstrated that one of the main problems which needed to be addressed was poor focusing of the beams and damage caused to optics due to the beam's extreme intensities caused by the optical Kerr effect, where, because the beam is so intense, that during its passage through either air or glass the electric field of the light actually alters the index of refraction of the material and causes the beam at the most intense points to "self focus" down to filament like structures of extremely high intensity. When a beam collapses into extremely high intensity filaments like this, it can easily exceed the laser damage threshold of laser glass and other optics, severely damaging them by creating pits, cracks and grey tracks through the glass.
This novel problem only became obvious as the lasers were scaled up in power to where nonlinear phenomena occur with very intense beams of light. LLNL's Krupke stated:
If the intensity of the light gets high enough —as in fusion lasers— the electric field in the light perturbs the atoms of the glass so strongly that the glass responds in a nonlinear way.
At the time there was no strong theoretical understanding of these effects, and predicting them was difficult. However, LLNL researchers combined their own efforts with those of the commercial glass vendors and were able to develop a new predictive tool which explained the relationship between the nonlinear effect intensity to all types of glass. As Krupke noted:
It was like the Rosetta stone. With this quantitative correspondence, they were able to plot the nonlinear refractive performance of millions of glasses and find the one with the lowest possible value. We then worked with our industrial partners to make a composition with the characteristics we needed.
Although using the proper glass was able to reduce the problem as much as possible, the problem still existed. For smaller experiments this would not be enough of an effect to worry about, but with the much larger and more powerful Shiva already under design, some way of further improving the beam smoothness of the laser needed to be studied.
The simplest way to eliminate these effects was to filter them out physically using what essentially amounts to a Fourier transform technique applied to the beam's spatial intensity profile. Imaging spatial filters are, in effect, small inverted telescopes inserted in the laser beam to focus the light through a pinhole. Many modes of spatial anisotropy would result in a very low angle of diffraction off the centerline however, so to improve the smoothing performance, the spatial filter tube is extremely long, thereby maximizing the distance the filaments moved from the centerline. Such a laser had not previously been built, the earlier Janus laser, which explored the Nd:glass laser itself, was only a few meters long.
It was precisely the problems of building a long laser that Cyclops was built to study. Cyclops was effectively a single-beam of the larger Shiva design, one that could be completed as quickly as possible in order to identify potential problems and come up with the best arrangement for the filters. In this goal Cyclops was successful, and every major ICF effort since has used the spatial filtering technique, leading to ever-growing laser "beamlines" on the order of 100 m today.
While Cyclops was still under construction, another LLNL laser was being built that also incorporated the spatial filtering technique, Argus. Argus passed its light through a series of amplifiers, with spatial filters between each stage and easily achieved terawatt beam powers.
See also
Laser
Lawrence Livermore National Laboratory
List of laser types
References
Laser Programs: the First 25 Years...1972-1997 (PDF)
External links
https://web.archive.org/web/20041109063036/http://www.llnl.gov/50science/lasers.html
http://www.osti.gov/bridge/servlets/purl/16710-UOC0xx/native/16710.pdf
http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1976lim..conf...18A&db_key=PHY&data_type=HTML&format=&high=44fac4eeaa06475
vte
Lawrence Livermore National Laboratory
Facilities
Mirror Fusion Test Facility
Tandem Mirror Experiment National Atmospheric Release Advisory Center National Energy Research Scientific Computing Center National Ignition Facility
Supercomputers
ASC Purple ASCI Blue Pacific ASCI White Peloton Sierra
Products
Lasers
Argus Cyclops Janus Long path Nova Novette Shiva
Others
Gist LLNL RISE process LX-14 Micropower impulse radar Reliable Replacement Warhead ROSE SCALD Silo Slapper detonator W47 W70 W71 Yorick
People
Ernest Lawrence Edward Teller
Related
IBM Blue Gene Inertial confinement fusion Laser Inertial Fusion Energy Stockpile stewardship Sustained Spheromak Physics Experiment Z-Division
vte
Fusion power, processes and devices
Core topics
Nuclear fusion
Timeline List of experiments Nuclear power Nuclear reactor Atomic nucleus Fusion energy gain factor Lawson criterion Magnetohydrodynamics Neutron Plasma
Processes,
methods
Confinement
type
Gravitational
Alpha process Triple-alpha process CNO cycle Fusor Helium flash Nova
remnants Proton-proton chain Carbon-burning Lithium burning Neon-burning Oxygen-burning Silicon-burning R-process S-process
Magnetic
Dense plasma focus Field-reversed configuration Levitated dipole Magnetic mirror
Bumpy torus Reversed field pinch Spheromak Stellarator Tokamak
Spherical Z-pinch
Inertial
Bubble (acoustic) Laser-driven Magnetized Liner Inertial Fusion
Fusor Polywell
Other forms
Colliding beam Magnetized target Migma Muon-catalyzed Pyroelectric
Devices, experiments
Magnetic confinement
Tokamak
International
ITER DEMO PROTO
Americas
Canada STOR-M United States Alcator C-Mod ARC
SPARC DIII-D Electric Tokamak LTX NSTX
PLT TFTR Pegasus Brazil ETE Mexico Novillo [es]
Asia,
Oceania
China CFETR EAST
HT-7 SUNIST India ADITYA SST-1 Japan JT-60 QUEST [ja] Pakistan GLAST South Korea KSTAR
Europe
European Union JET Czech Republic COMPASS GOLEM [cs] France TFR WEST Germany ASDEX Upgrade TEXTOR Italy FTU IGNITOR Portugal ISTTOK Russia T-15 Switzerland TCV United Kingdom MAST-U START STEP
Stellarator
Americas
United States CNT CTH HIDRA HSX Model C NCSX Costa Rica SCR-1
Asia,
Oceania
Australia H-1NF Japan Heliotron J LHD
Europe
Germany WEGA Wendelstein 7-AS Wendelstein 7-X Spain TJ-II Ukraine Uragan-2M
Uragan-3M [uk]
Italy RFX United States MST
Magnetized target
Canada SPECTOR United States LINUS FRX-L – FRCHX Fusion Engine
Other
Russia GDT United States Astron LDX Lockheed Martin CFR MFTF
TMX Perhapsatron PFRC Riggatron SSPX United Kingdom Sceptre Trisops ZETA
Inertial confinement
Laser
Americas
United States Argus Cyclops Janus LIFE Long path NIF Nike Nova OMEGA Shiva
Asia
Japan GEKKO XII
Europe
European Union HiPER Czech Republic Asterix IV (PALS) France LMJ LULI2000 Russia ISKRA United Kingdom Vulcan
Non-laser
Applications
Thermonuclear weapon
Pure fusion weapon
International Fusion Materials Irradiation Facility ITER Neutral Beam Test Facility
vte
Solid-state lasers
Distinct subtypes
Semiconductor laser
Yttrium aluminium garnet
Nd:YAG laser Er:YAG laser Nd:Cr:YAG Yb:YAG Nd:Ce:YAG Ho:YAG Dy:YAG Sm:YAG Tb:YAG Ce:YAG Ce:Gd:YAG Gd:YAG
Glass
Nd:glass Ytterbium glass 147Pm+3:Glass Er:Yb:Glass
Other gain media
Ruby laser Yttrium iron garnet (YIG) Terbium gallium garnet (TGG) Ti:sapphire laser Solid-state dye laser (SSDL/SSOL/SSDPL) Yttrium lithium fluoride (YLF)
Neodymium-doped yttrium lithium fluoride (Nd:YLF) Yttrium orthovanadate (YVO4)
Neodymium-doped yttrium orthovanadate (Nd:YVO4) Yttrium calcium oxoborate (YCOB)
Nd:YCOB laser Ce:LiSAF Ce:LiCAF Cr:ZnSe U:CaF2 Sm:CaF2 Yb:SFAP
Structures
Diode-pumped solid-state laser (DPSSL) Fiber laser Figure-8 laser Disk laser F-center laser
Specific lasers
Trident laser ZEUS-HLONS (HMMWV Laser Ordnance Neutralization System) Nova (laser) Cyclops laser Janus laser Argus laser Shiva laser HiPER Laboratory for Laser Energetics Laser Mégajoule LULI2000 Mercury laser ISKRA-6 Vulcan laser
Aspects
Mode-locking Energy transfer upconversion Solar-pumped laser
Laser types: Solid-state
Semiconductor Dye Gas
Chemical Excimer Ion Metal Vapor
vte
List of laser articles List of laser types List of laser applications Laser acronyms
Laser types: Solid-state
Semiconductor Dye Gas
Chemical Excimer Ion Metal Vapor
Laser physics
Active laser medium Amplified spontaneous emission Continuous wave Doppler cooling Laser ablation Laser cooling Laser linewidth Lasing threshold Magneto-optical trap Optical tweezers Population inversion Resolved sideband cooling Ultrashort pulse
Laser optics
Beam expander Beam homogenizer B Integral Chirped pulse amplification Gain-switching Gaussian beam Injection seeder Laser beam profiler M squared Mode-locking Multiple-prism grating laser oscillator Multiphoton intrapulse interference phase scan Optical amplifier Optical cavity Optical isolator Output coupler Q-switching Regenerative amplification
Laser spectroscopy
Cavity ring-down spectroscopy Confocal laser scanning microscopy Laser-based angle-resolved photoemission spectroscopy Laser diffraction analysis Laser-induced breakdown spectroscopy Laser-induced fluorescence Noise-immune cavity-enhanced optical heterodyne molecular spectroscopy Raman spectroscopy Second-harmonic imaging microscopy Terahertz time-domain spectroscopy Tunable diode laser absorption spectroscopy Two-photon excitation microscopy Ultrafast laser spectroscopy
Laser ionization
Above-threshold ionization Atmospheric-pressure laser ionization Matrix-assisted laser desorption/ionization Resonance-enhanced multiphoton ionization Soft laser desorption Surface-assisted laser desorption/ionization Surface-enhanced laser desorption/ionization
Laser fabrication
Laser beam welding Laser bonding Laser converting Laser cutting Laser cutting bridge Laser drilling Laser engraving Laser-hybrid welding Laser peening Multiphoton lithography Pulsed laser deposition Selective laser melting Selective laser sintering
Laser medicine
Computed tomography laser mammography Laser capture microdissection Laser hair removal Laser lithotripsy Laser coagulation Laser surgery Laser thermal keratoplasty LASIK Low-level laser therapy Optical coherence tomography Photorefractive keratectomy Photorejuvenation
Laser fusion
Argus laser Cyclops laser GEKKO XII HiPER ISKRA lasers Janus laser Laboratory for Laser Energetics Laser integration line Laser Mégajoule Long path laser LULI2000 Mercury laser National Ignition Facility Nike laser Nova (laser) Novette laser Shiva laser Trident laser Vulcan laser
Civil applications
3D laser scanner CD DVD Blu-ray Laser lighting display Laser pointer Laser printer Laser tag
Military applications
Advanced Tactical Laser Boeing Laser Avenger Dazzler (weapon) Electrolaser Laser designator Laser guidance Laser-guided bomb Laser guns Laser rangefinder Laser warning receiver Laser weapon LLM01 Multiple Integrated Laser Engagement System Tactical High Energy Laser Tactical light ZEUS-HLONS (HMMWV Laser Ordnance Neutralization System)
Hellenica World - Scientific Library
Retrieved from "http://en.wikipedia.org/"
All text is available under the terms of the GNU Free Documentation License
