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The Texas Petawatt Laser

Posted by kdawson on from the you-can-pet-a-dog-or-you-can-pet-a-cat dept.

Roland Piquepaille notes the hype surrounding what the University of Texas at Austin is calling the world's most powerful laser. During a tenth of a femtosecond this laser is 2,000 times more powerful than all the power plants in the US, and is brighter than sunlight on the surface of the Sun. On his own blog Roland points out that UT's is not the first petawatt laser; that distinction belongs to a system installed at Lawrence Livermore National Laboratory in 1996.

4 of 174 comments (clear)

  1. We're all wondering... by dj_tla · · Score: 5, Funny

    Will this laser have to be attached to significantly more powerful sharks?

    1. Re:We're all wondering... by yoavi · · Score: 5, Informative

      This is not accurate. Watts are indeed rates of energy consumption, that is, the amount of energy consumed per unit time (Watt stands for Joule per second). Now, if we squeeze 100 Joules in into 10^-13 of a second, then the *instantaneous* power during those 100 femtoseconds (and yes, the story has got it wrong, it's a tenth of a picosecond, not femtosecond, which makes a hundred femtoseconds) is one petawatt. The average power, assuming we operate at 0.1Hz (which I think will be the laser's repetition rate) is only 10 Watts.

      This also answers the "heating" problem. These lasers carry a relatively small amount of energy, and produce very little heat. However, the electric field that is produced when the beam is focused is huge, and many interesting phenomena can be studied with such a laser.

      Btw, for the same reason, this type of laser is completely useless as a weapon. In order to cause any real damage one has to deposit energy into the substance that is to be damaged, and again, these laser pulses carry a relatively small amount of energy.

  2. Obvious mistake in TFA by justkeeper · · Score: 5, Informative

    One femtoseocnd is 10 to the power of -15 of a second,NOT one trillionth of a second.Thus the pulse duration should be 100 fs,which is realistic.State of the art technology can't yet produce high power sub-femtosecond(i.e attosecond) pulses ,due to low conversion efficiency of energy concentrated on the low-frequency spectrum to the high-frequency spectrum using currently available methods(for an attosecond pulse a Fourier Transform will show that you have mostly X-ray frequency components in the frequency spectrum). Discaimer:I'm a Ph.D student working on high-power laser systems.

  3. Soon to be a Dime a Dozen by djtachyon · · Score: 5, Informative

    University of Rochester is building a petawatt laser of capable of picosecond pulse lengths. http://omegaep.lle.rochester.edu/

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