Graphite enters different states of matter

May 16, 2012 By Anne M. Stark
Demonstration of ultrafast disintegration of matter by 2 keV LCLS pulses: The team combined techniques commonly used in solid state physics (Bragg reflection) with techniques from plasma physics (spectroscopy of diffusely-scattered light) to characterize ultrafast heating in graphite.

( -- For the first time, scientists have seen an X-ray-irradiated mineral go to two different states of matter in about 40 femtoseconds (a femtosecond is one quadrillionth of a second).

Using the (LCLS) X-ray Free-Electron Laser (XFEL) at SLAC National Accelerator Laboratory at Stanford, Stefan Hau-Riege of Lawrence Livermore National Laboratory and colleagues heated graphite to induce a transition from solid to liquid and to warm-dense plasma.

Ultrafast from solid to liquid and plasma states are important in the development of new material-synthesis techniques, in ultrafast imaging, and high-energy density science.

By using different pulse lengths and calculating different spectra, the team was able to extract the time dependence of plasma parameters, such as electron and ion temperatures and ionization .

"We found that the heating and disintegration of the ion lattice occurs much faster than anticipated," Hau-Riege said.

The research provides new insights into the behavior of matter irradiated by intense hard X-rays. Though the study ultimately serves as a breakthrough in and ultrafast materials science, it also affects other fields such as single molecule biological imaging and X-ray optics.

For single-molecule bioimaging, the team found that in certain cases it may be substantially more difficult than anticipated because energy transfer is surprisingly fast. In X-ray optics, they found that the damage threshold is lower than anticipated.

This is the first XFEL high-energy density science experiment that used inelastic X-ray scattering as a plasma diagnostic.

The research is scheduled to appear in the May 21 edition Physical Review Letters.

Explore further: Synthesis of a new lean rare earth permanent magnetic compound superior to Nd2Fe14B

Related Stories

Early results from the world's brightest X-ray source

Jun 22, 2010

The first published scientific results from experiments at SLAC's Linac Coherent Light Source are out. The report, published today in Physical Review Letters, is the first look at how molecules respond to ult ...

FLASH Imaging Redux: Nano-Cinema is Born

Jul 08, 2008

Flash imaging of nanoscale objects undergoing ultrafast changes is now a technical possibility, according to a recent paper published in the June 22 edition of Nature Photonics. The results are a direct precur ...

LCLS: The World's Largest Laser Writer?

Oct 20, 2009

( -- While not the smallest lettering ever created, the tiny initials "LCLS" have been written with what may be the world's most potent pen. Etched into boron carbide, a super-hard substance used ...

Recommended for you

Scientists develop compact medical imaging device

4 hours ago

Scientists at the MIRA research institute, in collaboration with various companies, have developed a prototype of a handy device that combines echoscopy (ultrasound) with photoacoustics. Combining these two ...

User comments : 0