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World's Most Powerful Laser
mattlary writes "The Rochester Democrat and Chronicle reports that the University of Rochester plans on building the world's most powerful laser. The plans include upgrading the University's Omega laser with a pair of petawatt lasers. Sounds a lot like Real Genius to me."
Haven't the comic stylings of Chris Knight, Mitch Whazzisname, and freaky guru Lazlo taught us anything? This can only lead to a house full of popcorn :)
std::disclaimer<std::legalese> sig=new std::disclaimer; sig->dump(); delete sig;
Here's some information about NIF, Lawrence Livermore's laser facility: http://www.llnl.gov/nif/ The lasers here use more than 1000 times the possible electric output of the United States in one burst (through capacitors.) (1.8MJ) Lawrence Livermore dismantled their Petawatt laser to build NIF, which is bigger and shinier, and therefore much, much better. : ) (It's also not finished yet-- 5 years, or so)
Here's a site that explains how it works: http://www.llnl.gov/nif/nifworks/index.html
The article does mention NIF, but only at the bottom, briefly. It is not to be overlooked. I've been through the facility -- it's absolutely massive. Full of wondrously expensive and very shiny toys.
U of R is right down the street from me (I go to RIT). I read this story yesterday and hear that it stil has to get approval from the town to build this thing. I bet that they will get it as it brings in alot of money from the goverment, but it's not defenite for sure yet. BEN
using fission power is not that popular
It would also be wholly impractical in this case.
What is required, as you say, is to raise the hydrogen to a suitably high temperature and pressure. The laser is used not only to increase the temperature of your target material, but also the pressure (the sudden increase in temperature causes the surface to ablate, which causes an increase in pressure on the remainder of the target). To achieve the same effect using a fission reaction, you would essentially have to create an explosion, which would be *far* harder to do safely. You're likely to just destory the reactor, as only a small fraction of the total output energy of the explosion could actually be directed at the target.
In an H-bomb, of course, the more destructive the reaction the better.
It's official. Most of you are morons.
A petawatt is one petajoule/second. So, are you impressed yet? Or do you want some frickin' sharks thrown in there too?
Picky.
-Colin
Indeed.
:-)
A few years ago, I started a PhD in plasma physics, studying the high speed electron transport effects in short pulse, high intensity laser-plasma interactions. You are of course quite correct in your assertion that this sort of laser fires extremely brief pulses.
In plamsa physics, such a pulse is used to rapidly (read, near-instanteously) heat the surface of a target. The rapid heating causes the surface to ablate, which in turn causes the rest of the target to be compressed and heated. Get it right, and fusion ocurrs.
Quite apart from the physical reasons why you'd use a short pulse, the ultimate goal here is to create a viable method of producing energy. The more energy you put in at the start (by using a "long" laser pulse), the more you have to get out in the long run to make it worthwhile.
When I was still on my PhD (before I got bored and quit), we had a working z-pinch in the basement. As dramatic as it would have been for the lights to dim, there were no outward signs when it was fired
It's official. Most of you are morons.
I think they plan on dealing with this by using vanadium alloys. If you start with the most stable form of vanadium (V51) and bombard it with neutrons, the first neutron absorbed will cause a quick beta decay to Cr52. Fortunately, chromium has the same crystal structure as V, so you won't weaken the alloy much. Cr can absorb another 3 neutrons before it beta-decays to Mn55, which has a different crystal structure, so at that point, you might start causing enbrittlement of the alloy. However, Mn55 can absorb 5 more neutrons before you end up with an element that has a worrying half life (Co60).
So by picking your materials correctly, you can potentially avoid some of the problems associated with neutrons.
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The internet is the greatest source of biased information in the history of mankind.
As a technician on the Omega Laser I guess have a bit of an inside track on what's going on around the LLE.
First you must make a distinction between most powerful(energy/time) laser and most energetic(energy per pulse) laser, this is a distinction not made in the article. The Omega laser is currently the most energetic ultraviolet(frequency tripled Neodymium:Glass) laser in the world now at ~25 Kilojoules per pulse, very soon to be eclipsed by the preliminary first light of the National Ignition Facility. However each "shot" on the system, as they are called, is only a couple hundred picoseconds to a couple nanoseconds long (depending on the shot pulse shape) making it's peak power around a maximum of about 60 Terawatts. This is not the most powerful laser in the world. The Rutherford Appelton laboratory in England has a "Petawatt" system they just commissioned which is capable of at least hundreds of Terawatts of power albeit only with a couple hundred joules of energy per shot.
It is interesting to note that the mechanism the Petawatt upgrade at the LLE will use to achieve it's million billion watts of power in a pulse time of a few picoseconds to hundreds of femtoseconds is called Optical Parametric Chirped Pulse Amplification(OPCPA) and was invented right at THE UofR in the late 1980's!! Chirped Pulse Amplification lasers are the only means to get to petawatt intensities and they are interesting because they are the first technology to allow nuclear reactions to be directly caused by intense light radiation(ie. no implosion/ heating stage as in ICF). This is really interesting because in addition to the spark plug type inertial confinement fusion catalyzing experiments that are planned, the intensity fluences allowed by petawatt lasers approaches (possibly >10^21 watts/sq. inch) what is necessary to do an experiment called "sparking the vacuum" whereby enough energy is placed in a small enough volume of space in a short enough period of time to cause a spontaneous transformation of energy directly into particles(via E=Mc^2). Neat eh?
- "Hear that?! The percolations are imminent! Cease your ingress!"
No, the Russian word for bottle is "butil`", with soft "l" at the end. That is, IIRC, Russian is not my first language. But tokamak is not bottle in Russian for sure.
According to this link
http://ippex.pppl.gov/fusion/glossary.html
> Knight deflating Kent was the best part of that film.
No, the cute, nerdly love interest with the dark hair and the full lips was the best, indeed only decent, part of that movie.
"Has [being a kidnapped teenage girl, raped repeatedly for months] changed you?" - Katie Couric to Elizabeth Smart
Well, actually, this not the kind of lasers you're interested in if you want to shoot down rockets. A laser this strong would heat up a small patch of the rocket for only a very short time (maybe triggering some fusion reaction along the way), and would hardly result in the desired effect. You'd rather want an industrial laser which the yuse to cut metals, which would literally cut the missille, and probably ignite any flammable materials inside (i.e. the warhead or the propellant).