Format

Send to

Choose Destination
Phys Rev Lett. 2008 Aug 15;101(7):077401. Epub 2008 Aug 12.

Direct observation of optically induced transient structures in graphite using ultrafast electron crystallography.

Author information

1
Physics and Astronomy Department, Michigan State University, East Lansing, Michigan 48824-2320, USA.

Abstract

We use ultrafast electron crystallography to study structural changes induced in graphite by a femtosecond laser pulse. At moderate fluences of < or =21 mJ/cm2, lattice vibrations are observed to thermalize on a time scale of approximately 8 ps. At higher fluences approaching the damage threshold, lattice vibration amplitudes saturate. Following a marked initial contraction, graphite is driven nonthermally into a transient state with sp3-like character, forming interlayer bonds. Using ab initio density functional calculations, we trace the governing mechanism back to electronic structure changes following the photoexcitation.

Supplemental Content

Full text links

Icon for American Physical Society
Loading ...
Support Center