1. MTA‐PTE High‐Field Terahertz Research Group 7624 Pécs Hungary
2. ELI‐ALPSELI‐HU Nonprofit Ltd. 6720 Szeged Hungary
3. Szentágothai Research CentreUniversity of Pécs 7624 Pécs Hungary
4. Science ProgramTexas A&M University at Qatar P.O. Box 23874 Doha Qatar
5. Materials Science and Technology DepartmentUniversity of Crete 71003 Heraklion Greece
6. Institute of Electronic Structure and LaserFoundation for Research and Technology Hellas 71110 Heraklion Greece
7. Department of PhysicsFreie Universität Berlin 14195 Berlin Germany
8. Department of Physical ChemistryFritz Haber Institute of the Max Planck Society 14195 Berlin Germany