Ultrafast changes in lattice symmetry probed by coherent phonons.

@article{Wall2012UltrafastCI,
  title={Ultrafast changes in lattice symmetry probed by coherent phonons.},
  author={Simon Wall and Daniel Wegkamp and Laura Foglia and Kannatassen Appavoo and Joyeeta Nag and Richard F. Haglund and Julia St{\"a}hler and Martin Wolf},
  journal={Nature communications},
  year={2012},
  volume={3},
  pages={
          721
        }
}
The electronic and structural properties of a material are strongly determined by its symmetry. Changing the symmetry via a photoinduced phase transition offers new ways to manipulate material properties on ultrafast timescales. However, to identify when and how fast these phase transitions occur, methods that can probe the symmetry change in the time domain are required. Here we show that a time-dependent change in the coherent phonon spectrum can probe a change in symmetry of the lattice… Expand
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