TY  - EJOUR
AU  - Schwickert, David
AU  - Ruberti, Marco
AU  - Kolorenč, Přemys
AU  - Usenko, Sergey
AU  - Przystawik, Andreas
AU  - Baev, Karolin
AU  - Baev, Ivan
AU  - Braune, Markus
AU  - Bocklage, Lars
AU  - Czwalinna, Marie Kristin
AU  - Deinert, Sascha
AU  - Düsterer, Stefan
AU  - Hans, Andreas
AU  - Hartmann, Gregor
AU  - Haunhorst, Christian
AU  - Kuhlmann, Marion
AU  - Palutke, Steffen
AU  - Roehlsberger, Ralf
AU  - Rönsch-Schulenburg, Juliane
AU  - Schmidt, Philipp
AU  - Toleikis, Sven
AU  - Viefhaus, Jens
AU  - Martins, Michael
AU  - Knie, Andre
AU  - Kip, Detlef
AU  - Averbukh, Vitali
AU  - Marangos, Jon
AU  - Laarmann, Tim
TI  - Electronic Quantum Coherence in Glycine Molecules Probed with Ultrashort X-ray Pulses in Real Time
IS  - arXiv:2012.04852
M1  - PUBDB-2022-02957
M1  - arXiv:2012.04852
PY  - 2020
N1  - 61 pages, 12 figures
AB  - Quantum coherence between electronic states of a photoionized molecule and the resulting process of ultrafast electron-hole migration have been put forward as a possible quantum mechanism of charge-directed reactivity governing the photoionization-induced molecular decomposition. Attosecond experiments based on the indirect (fragment ion-based) characterization of the proposed electronic phenomena suggest that the photoionization-induced electronic coherence can survive for tens of femtoseconds, while some theoretical studies predict much faster decay of the coherence due to the quantum uncertainty in the nuclear positions and the nuclear-motion effects. The open questions are: do long-lived electronic quantum coherences exist in complex molecules and can they be probed directly, i.e. via electronic observables? Here, we use x-rays both to create and to directly probe quantum coherence in the photoionized amino acid glycine. The outgoing photoelectron wave leaves behind a positively charged ion that is in a coherent superposition of quantum mechanical eigenstates lying within the ionizing pulse spectral bandwidth. Delayed x-ray pulses track the induced coherence through resonant x-ray absorption that induces Auger decay and by the photoelectron emission from sequential double photoionization. Sinusoidal temporal modulation of the detected signal at early times (0 - 25 fs) is observed in both measurements. Advanced ab initio many-electron simulations, taking into account the quantum uncertainty in the nuclear positions, allow us to explain the first 25 fs of the detected coherent quantum evolution in terms of the electronic coherence.
KW  - photoelectron, emission (INSPIRE)
KW  - coherence (INSPIRE)
KW  - nucleus (INSPIRE)
KW  - spectral (INSPIRE)
KW  - long-lived (INSPIRE)
KW  - modulation (INSPIRE)
KW  - Auger (INSPIRE)
KW  - quantum mechanics (INSPIRE)
KW  - ion (INSPIRE)
KW  - tracks (INSPIRE)
KW  - absorption (INSPIRE)
KW  - X-ray (INSPIRE)
LB  - PUB:(DE-HGF)25
DO  - DOI:10.3204/PUBDB-2022-02957
UR  - https://bib-pubdb1.desy.de/record/479274
ER  -