Photoelectron spectroscopies (PES) and in particular angle-resolved photoelectron spectroscopies (ARPES) provide powerful probes for investigating quasiparticle dynamics in correlated-electron materials. High harmonic EUV sources are ideal for ARPES for several reasons –

  • Their photon energy and momentum can probe band-specific dynamics across the entire Brillouin zone
  • They can be implemented with very high repetition rates (1-100kHz) to eliminate space charge distortion, and also enable spin-resolved ARPES
  • They are perfectly synchronized to the driving laser, with the ability to capture the fastest sub-femtosecond charge and spin dynamics
  • EUV high harmonics can experimentally access quasiparticle lifetimes, electron mean free paths, electron-electron scattering and dynamical screening, all of which represent science grand challenges
  • Their polarization state is well defined, and can be adjusted from linear (s & p) to circular polarization to harness photoemission selection rules
  • Sequences of attosecond pulses are superior to isolated attosecond pulses for measuring band-specific electron dynamics with 100meV energy resolution and 20 attosecond time resolution
Mott Insulator

Example References:

Science 353, 62 (2016)

Science 353, 28 (2016)

Science Advances, in press (2017)

Nature 471, 490 (2011)

Nat. Comm 3, 1069 (2012)

PRL 112 , 207001 (2014)

PRB 92, 041407 (2015)

Nature Comm. 7, 12902 (2016)