Ultrafast photocurrents at the surface of the three-dimensional topological insulator Bi2Se3

@article{Braun2016UltrafastPA,
  title={Ultrafast photocurrents at the surface of the three-dimensional topological insulator Bi2Se3},
  author={Lukas Braun and Gregor Mussler and A. Hruban and Marcin Konczykowski and T. Schumann and Martin Wolf and Markus M{\"u}nzenberg and Luca Perfetti and Tobias Kampfrath},
  journal={Nature Communications},
  year={2016},
  volume={7}
}
Three-dimensional topological insulators are fascinating materials with insulating bulk yet metallic surfaces that host highly mobile charge carriers with locked spin and momentum. Remarkably, surface currents with tunable direction and magnitude can be launched with tailored light beams. To better understand the underlying mechanisms, the current dynamics need to be resolved on the timescale of elementary scattering events (∼10 fs). Here, we excite and measure photocurrents in the model… 
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