Space Charge Free Ultrafast Photoelectron Spectroscopy on Solids by a Narrowband Tunable Extreme Ultraviolet Light Source
preprint
posted on 2023-11-30, 19:03 authored by Riccardo Cucini, Tommaso Pincelli, Giancarlo Panaccione, Damir Kopic, Fabio Frassetto, Paolo Miotti, Gian Marco Pierantozzi, Simone Peli, Andrea Fondacaro, Aleksander De Luisa, Alessandro De Vita, Pietro Carrara, Damjan Krizmancic, Daniel T. Payne, Federico Salvador, Andrea Sterzi, Luca Poletto, Fulvio Parmigiani, Giorgio Rossi, Federico CilentoHere we report on a novel High Harmonic Generation (HHG) light source designed for space charge free ultrafast photoelectron spectroscopy (PES) on solids. The ultimate overall energy resolution achieved on a polycrystalline Au sample is ~22 meV at 40 K. These results have been obtained at a photon energy of 16.9 eV with a pulse bandwidth of ~19 meV, by varying, up to 200 kHz, the photon pulses repetition rate and the photon fluence on the sample. These features set a new benchmark for tunable narrowband HHG sources. By comparing the PES energy resolution and the photon pulse bandwidth with a pulse duration of ~105 fs, as retrieved from time-resolved (TR) angle resolved (AR) PES experiments on Bi$_2$Se$_3$, we validate a way for a space charge free photoelectric process close to Fourier transform limit conditions for ultrafast TR-PES experiments on solids.
