Performing time and angle resolved photoemission spectroscopy (tr-ARPES) at high momenta necessitates extreme ultraviolet laser pulses, which are typically produced via high harmonic generation (HHG). Despite recent advances, HHG-based setups still require large pulse energies (hundreds of μJ to mJ) and their energy resolution is limited to tens of meV. Here, we present a novel 11 eV tr-ARPES setup that generates a flux of 5×1010 photons/s and achieves an unprecedented energy resolution of 16 meV. It can be operated at high repetition rates (up to 250 kHz) while using input pulse energies down to 3 μJ. We demonstrate these unique capabilities by simultaneously capturing the energy and momentum resolved dynamics in two well-separated momentum space regions of a charge density wave material ErTe3. This novel setup offers opportunity to study the non-equilibrium band structure of solids with exceptional energy and time resolutions at high repetition rates.
@article{arxiv.1910.14068,
title = {High resolution time- and angle-resolved photoemission spectroscopy with 11 eV laser pulses},
author = {Changmin Lee and Timm Rohwer and Edbert J. Sie and Alfred Zong and Edoardo Baldini and Joshua Straquadine and Philip Walmsley and Dillon Gardner and Young S. Lee and Ian R. Fisher and Nuh Gedik},
journal= {arXiv preprint arXiv:1910.14068},
year = {2020}
}