U of MI Produces Strongest Laser Ever

eldavojohn writes "Weighing in at a mere 20 billion trillion watts per square centimeter and containing a measly 300 terawatts of power, the University of Michigan has broken a record with a 1.3-micron speck wide laser. It's about two orders of magnitude higher than any other laser in the world and can perform for 30 femtoseconds once every ten seconds — some of the researchers speculate it is the most powerful laser in the universe. 'If you could hold a giant magnifying glass in space and focus all the sunlight shining toward Earth onto one grain of sand, that concentrated ray would approach the intensity of a new laser beam made in a University of Michigan laboratory ... To achieve this beam, the research team added another amplifier to the HERCULES laser system, which previously operated at 50 terawatts. HERCULES is a titanium-sapphire laser that takes up several rooms at U-M's Center for Ultrafast Optical Science. Light fed into it bounces like a pinball off a series of mirrors and other optical elements. It gets stretched, energized, squeezed and focused along the way.'" And ... cue the evil chortling.

all these strange figures

[howlingmadhowie]

20 billion trillion watt per square centimeter = 2x10^26 Wm^-2
300 terawatt of power = 3x10^14 W
1.3 micron wide = ca. 1.7x10^-12 m^2 (for a square shape)
30 femtosecond = 3x10^-14 s

hope that clarifies things.

FS-Lasers are cool beasts

[imsabbel]

Because focussed correctly, the extremely high field strenght in the focal point can create effects that at first seem physically implausible.

For example there is one effect that seems to "break" quantum phyiscs (or more exactly, the photo-effect): You can excite electrons out of energy levels that are bound stronger than the photon energy. Even if they are bound _a_ lot stronger. The electric fields can be strong enough to strip atoms from everything down to and including the k-shell (I have one seen a presenter show a silde mentioning 37-photon effects...)
This can be used to create hard x-rays, or, of course, as a particle accelerator: You can GeV on ion energyies from them with a relatively simple setup.

This is of course for "normal" FS-Lasers, wich fill not much more than a large optical bank. But something tells me that _this_ one can make even more intersting stuff happen :)

Re:all these strange figures

[Anonymous Coward]

You should use the <quote> tags instead of italics for quoting now.

Re:So what can you do with it?

[Detritus]

There is a lot of interesting materials science done with lasers that produce very short and very intense pulses of light. This laser might be useful for something like that. There is also the possibility of using it for long distance communication or ranging. Radar systems get decent range by transmitting short pulses of RF at very high power levels. The average power is low enough to keep power consumption and heat dissipation at manageable levels.

Re:Safety first

[Anonymous Coward]

According to the paper, the total output energy is only 17 joules (watt-seconds). It wouldn't do anything at all to anything you aimed at it. When they fire it, they need special instruments just to detect that anything happened.

Re:In the universe?

[TapeCutter]

I think they were refering to the known universe and alluding to natural lasers [google.com.au].

In contrast the best particle beams on the planet get a few gold atoms to near light speed, while the natural ones can easily get the planet Jupiter moving at that pace.

... and that amounts to

[ebcdic]

... 9 Joules delivered in each pulse, one every 10 seconds. Giving an average power of about 1 Watt. Ideal for taking over very small universes.

Re:FS-Lasers are cool beasts

[ortholattice]

I found out later that my hunch was correct - it's just unlikely for two photons to hit an atom at exactly the same (to within a plancks time) with a low powered laser.

A Planck time (10^-43 s)? How do you conclude that number?

If you shine two beams so that they cross paths, some photons will collide with each other and scatter.

The actual mechanism, I believe, is that a photon can momentarily fluctuate into a charged fermion/antifermion pair, and the cross-beam interacts with those particles.

Re:all these strange figures

[Mike1024]

300 terawatt of power = 3x10^14 W
30 femtosecond = 3x10^-14 s

The duty cycle is 30 femtoseconds per 10 seconds.

If the '300 terrawatts' of power is consumed for 30 femtoseconds per 10 seconds, the average power consumption over 10 seconds is (3 * ((10^14) W) * 3 * ((10^(-14)) s)) / (10 s) = 0.9 watts

If, on the other hand, the 300 terrawatts is the average power consumption over 10 seconds, the power consumption when the laser is on is (3 * ((10^14) W) * (10 s)) / (3 * (10^(-14)) s) = 1.0 × 10^29 watts = 100,000 yottawatts

Yotta- is the largest SI prefix, and the total energy output of the Sun is 383 YW.

I suspect the former interpretation is more likely. This laser isn't so impressive when you realise it takes less power than my computer monitor... when my computer monitor is turned off.

Re:So what can you do with it?

[cecil_turtle]

Obligatory xkcd reference [xkcd.com].

Re:Safety first

[evanbd]

17 joules is plenty of energy to detect without special instruments. It's enough to vaporize about 6 mg of water, or in other words it could blast a spherical hole about 1/16" diameter in your finger -- which I think you'd notice. Granted, it's not a lot of energy, but it's not a trivial amount, either.

Rubbish

[littleghoti]

Article is wrong. Vulcan in the UK is a 1 petawatt laser, which is 3 times more powerful, and has been running since 2004:
http://www.clf.rl.ac.uk/news/CLF_News/vulcanpetawatt.htm [rl.ac.uk]

They even have a plaque from the Guinness book of records.

Depends what you're measuring.

[DTemp]

The Vulcan has more power (wattage). But this UofMI laser focuses the blast onto a smaller area, and it lasts less than 1/10th the time. So, the beam is more intense.

Re:Not so cool

[Cederic]

Chasing Amy is better than Mallrats and Dogma - wittier, more based in reality (one thing that made Clerks so effective - it was very believable) and the characters are easily identified with. Well, sort of. Their confusion and emotional state is easily identified with.

The Princess Bride is however worth seeking out. The sheer number of quotes (and misquotes) on the internet from that one film make it worth watching alone (so you can understand what they're all on about) but it also happens to be fantastically well written, very witty, nicely acted, beautifully shot and features some great insults, classy one-liners, a hero you want to believe in and a sword fight that'll leave you breathless.

Damnit, now I'm going to have to go and watch it again myself - yet another reason I can't watch Real Genius. I am however impressed at the size of this very offtopic thread of conversation in a discussion on high powered lasers.