Enhanced ultrafast relaxation rate in the Weyl semimetal phase of MoTe2 measured by time- and angle-resolved photoelectron spectroscopy

  title={Enhanced ultrafast relaxation rate in the Weyl semimetal phase of MoTe2 measured by time- and angle-resolved photoelectron spectroscopy},
  author={Alberto Crepaldi and Gabriel Aut{\`e}s and G. Gatti and Silvan Roth and Andrea Sterzi and Giulia Manzoni and Michele Zacchigna and Cephise Cacho and Richard T. Chapman and Emma Springate and Elaine A. Seddon and Philippe Bugnon and Arnaud Magrez and Helmuth Berger and Ivana Vobornik and M. Kallane and A. Quer and Kai Rossnagel and Fulvio Parmigiani and Oleg V. Yazyev and M. Grioni},
  journal={Physical Review B},
$\mathrm{MoTe_2}$ has recently been shown to realize in its low-temperature phase the type-II Weyl semimetal (WSM). We investigated by time- and angle- resolved photoelectron spectroscopy (tr-ARPES) the possible influence of the Weyl points in the electron dynamics above the Fermi level $\mathrm{E_F}$, by comparing the ultrafast response of $\mathrm{MoTe_2}$ in the trivial and topological phases. In the low-temperature WSM phase, we report an enhanced relaxation rate of electrons optically… 

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I and J

Nature 527

  • 495
  • 2015

and E

  • F. W. Jr., J. Chem. Thermodynamics 24, 627
  • 1992

Acta Crystallographica 20

  • 268
  • 1966


  • Rev. B 92, 161107
  • 2015


  • Rev. Lett. 117, 066402
  • 2016

Notice that the orthorhombic phase is also referred to as γ phase

    See the supplementary information for more details about the MoTe2 crystal characterization and the calculated and measured band structure of MoTe2 in the 1T' and1T" phases

      C: Solid State Phys

      • 11, L103
      • 1978


      • Rev. Lett. 117
      • 2016