The authors thank M. Billon for technical support. We acknowledge support from the PETACom (Petahertz Optoelectronics Communication) FET Open H2020 Grant No. 829153, OPTOLogic (Optical Topologic Logic) FET Open H2020 Grant No. 899794, support from the French ANR through the grant PACHA (No. ANR-17-CE30-0008-01) and the labex PALM (No. ANR-10-LABX-0039-PALM), support the DGA RAPID grant “SWIM.” We acknowledge the financial support from the French ASTRE program through the “NanoLight” grant, the Spanish Ministry MINECO (National Plan 15 grant: FISICATEAMO No. FIS2016-79508-P, SEVERO OCHOA No. SEV-2015-0522, FPI), European Social Fund, Fundació Cellex, Fundació Mir-Puig, Generalitat de Catalunya (AGAUR Grant No. 2017 SGR 1341, CERCA/Program), ERC AdG NOQIA, EU FEDER, European Union Regional Development Fund-ERDF Operational Program of Catalonia 2014–2020 (Operation Code: IU16-011424), MINECO-EU QUANTERA MAQS [funded by The State Research Agency (AEI) No. PCI2019-111828-2/10.13039/501100011033], and the National Science Centre, Poland-Symfonia Grant No. 2016/20/W/ST4/00314. F.N. and U.T. acknowledge support from Air Force Office of Scientific Research under Award No. FA9550-17-1-0369 and NSF Grant No. 1802085 (theory for photoemission from surfaces). Any opinions, finding, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the United States Air Force. U.T. acknowledges partial support from the Chemical Sciences, Geosciences, and Biosciences Division, Office of Basic Energy Sciences, Office of Science, US Department of Energy under Award No. DEFG02-86ER13491. N.T.-D. thanks A. Rubio.