Sunday, May 14, 2006

Record-breaking laser is hot stuff - The record for the fastest rise in temperature has just been topped.

"With the heat of a burning sun, a laser pulse has ripped through pure sapphire, heating it faster than any explosion ever recorded.

The experiment was a blast, say physicists who reckon their laser can drive temperature increases of a billion billion (1018) degrees per second, although they could only keep it going for a couple of hundred femtoseconds (with a femtosecond being 10-15 s). That tops the previous heating-rate record, they say.

The intense heating power of the laser made miniature fireballs, just thousandths of a millimetre in size, at pressures of 10 terapascals (1013 Pa). That's about 20 times the pressure at the Earth's core. Although more powerful lasers have previously managed to create greater pressures, these required large, specialized facilities.

The intense crush also raised the temperature to about half a million °C. 'You have the same parameters in an atomic explosion,' says Vladimir Tikhonchuk, a theoretical physicist from the University of Bordeaux, France.

The success shows that scientists can now simulate the intense condition at the hearts of planets, or possibly even trigger fusion reactions, using a conventional tabletop laser."

1 comment:

  1. Anonymous4:47 PM

    I accidentally stumbled into 'his nibs' site and have found it facinating...I did not know what a femtosecond was, nor a terapascal .. both of which will be looked up as soon as I go off this site.