TY  - JOUR
AU  - Diesen, Elias
AU  - Wang, Hsin-Yi
AU  - Schreck, Simon
AU  - Weston, Matthew
AU  - Ogasawara, Hirohito
AU  - LaRue, Jerry
AU  - Perakis, Fivos
AU  - Dell’Angela, Martina
AU  - Capotondi, Flavio
AU  - Giannessi, Luca
AU  - Pedersoli, Emanuele
AU  - Naumenko, Denys
AU  - Nikolov, Ivaylo
AU  - Raimondi, Lorenzo
AU  - Spezzani, Carlo
AU  - Beye, Martin
AU  - Cavalca, Filippo
AU  - Liu, Boyang
AU  - Gladh, Jörgen
AU  - Koroidov, Sergey
AU  - Miedema, Piter
AU  - Costantini, Roberto
AU  - Heinz, Tony F.
AU  - Abild-Pedersen, Frank
AU  - Voss, Johannes
AU  - Luntz, Alan C.
AU  - Nilsson, Anders
TI  - Ultrafast Adsorbate Excitation Probed with Subpicosecond-Resolution X-Ray Absorption Spectroscopy
JO  - Physical review letters
VL  - 127
IS  - 1
SN  - 0031-9007
CY  - College Park, Md.
PB  - APS
M1  - PUBDB-2022-00404
SP  - 016802
PY  - 2021
AB  - We use a pump-probe scheme to measure the time evolution of the C K-edge x-ray absorption spectrum from CO/Ru(0001) after excitation by an ultrashort high-intensity optical laser pulse. Because of the short duration of the x-ray probe pulse and precise control of the pulse delay, the excitation-induced dynamics during the first picosecond after the pump can be resolved with unprecedented time resolution. By comparing with density functional theory spectrum calculations, we find high excitation of the internal stretch and frustrated rotation modes occurring within 200 fs of laser excitation, as well as thermalization of the system in the picosecond regime. The ∼100  fs initial excitation of these CO vibrational modes is not readily rationalized by traditional theories of nonadiabatic coupling of adsorbates to metal surfaces, e.g., electronic frictions based on first order electron-phonon coupling or transient population of adsorbate resonances. We suggest that coupling of the adsorbate to nonthermalized electron-hole pairs is responsible for the ultrafast initial excitation of the modes.
LB  - PUB:(DE-HGF)16
C6  - 34270277
UR  - <Go to ISI:>//WOS:000669052000016
DO  - DOI:10.1103/PhysRevLett.127.016802
UR  - https://bib-pubdb1.desy.de/record/473986
ER  -