Forthcoming Events

11.07.2022 - 15.07.2022, Celeste Hotel, on UCF main campus, Orlando, Florida
05.09.2022 - 09.09.2022, Iseolago hotel, Iseo, Italy.


MUST2022 Conference- succesfully concluded
New scientific highlights- by MUST PIs Chergui and Richardson
FELs of Europe prize for Jeremy Rouxel- “Development or innovative use of advanced instrumentation in the field of FELs”
Ruth Signorell wins Doron prizefor pioneering contributions to the field of fundamental aerosol science
New FAST-Fellow Uwe Thumm at ETH- lectures on Topics in Femto- and Attosecond Science
International Day of Women and Girls in Science- SSPh asked female scientists about their experiences
New scientific highlight- by MUST PIs Milne, Standfuss and Schertler
EU XFEL Young Scientist Award for Camila Bacellar,beamline scientist and group leader of the Alvra endstation at SwissFEL
Prizes for Giulia Mancini and Rebeca Gomez CastilloICO/IUPAP Young Scientist Prize in Optics & Ernst Haber 2021
Nobel Prize in Chemistry awarded to RESOLV Member Benjamin List- for the development of asymmetric organocatalysis
NCCR MUST at Scientifica 2021- Lightning, organic solar cells, and virtual molecules
#NCCRWomen- NCCR MUST celebrates 50 years women’s right to vote in Switzerland
Kick-Off dynaMENT Mentoring for Women in Natural Sciences- with Ursula Keller as plenary speaker

Dynamics of valence-shell electrons and nuclei probed by strong-field holography and rescattering

June 15, 2017

Imaging ultrafast dynamics of molecules on femtosecond to attosecond timescales

Time-resolved measurements of molecular dynamics have made substantial progress over the past years. In particular, electronic dynamics in atoms and molecules have become accessible through recent developments in attosecond and strong-field science. In this study, the authors transposed photoelectron holography and LIED from static systems to probing coupled electronic and nuclear dynamics in molecules. They first concentrated on purely electronic dynamics and show that a valence-shell electron wave packet leads to a very strong contrast modulation of the holographic fringes. Their calculations traced the origin of this effect to the time dependence of the momentum-space electron wavefunction, which modulates the amplitude ratio and the relative phases of scattering and non-scattering trajectories. They then investigated the manifestation of coupled electronic and nuclear dynamics taking place on similar time scales. They found signatures of both types of dynamics in photoelectron holography, but LIED is found to be almost exclusively sensitive to the nuclear dynamics. These results suggest avenues for disentangling electronic and nuclear dynamics in molecules, which is particularly interesting in the case of non-adiabatic dynamics, such as those occurring at conical intersections.

Figure 1: Discerning electronic and nuclear dynamics. (a) The top panel illustrates the prepared electronic and rotational dynamics with the left part showing the time-evolution of the one-electron wave function in NO and the right part illustrating the molecular-axis distribution. The wave function can be chosen real-valued with opposite signs (red and blue) by multiplication with a global phase factor that corresponds to a physically irrelevant shift of the absolute energy scale. The middle panel shows the time-dependent normalized NO+ yield (blue line) and a sine function with a period of 277 fs (red line). The lowest panel shows the calculated alignment dynamics expressed by 〈cos2θ〉 (including volume averaging). (b) Photoelectron momentum distribution of excited NO molecules recorded at a delay of 1.56 ps. Normalized difference S(t1, t2) (defined in the text) of momentum distributions measured at the minimum and maximum of the NO+ signal dominated by electronic dynamics (c, t1=1.56 ps and t2=1.72 ps, respectively) or around the rotational revival (d, at t1=4.91 ps and t2=5.10 ps, respectively). a.u., atomic units.

Reference:  Walt, S. G., N. Bhargava Ram, M. Atala, N. I. Shvetsov-Shilovski, A. von Conta, D. Baykusheva, M. Lein and H. J. Wörner (2017). Dynamics of valence-shell electrons and nuclei probed by strong-field holography and rescattering.  8: 15651. (10.1038/ncomms15651) Walt-2017 (2.65 MB)

NCCR MUST Office : ETHZ IQE/ULP-HPT H3 | Auguste-Piccard-Hof 1 | 8093 Zurich | E-Mail | +41 44 633 36 02
The National Centres of Competence in Research (NCCR) are a research instrument of the Swiss National Science Foundation