Quantum Dynamics in Tailored Intense Fields Annual Workshop 26th February – 28th February 2020 Venue: Max-Born-Institut (MBI) Berlin Max-Born-Saal Max-Born-Straße 2A 12489 Berlin Wednesday, 26th February 2020 10:15 – 11:00 Tutorial Tobias Witting 11:00 – 11:45 Tutorial Mikhail Ivanov 11:45 – 12:35 Registration / lunch 12:35 – 12:45 Welcome Nirit Dudovich 12:45 – 13:20 Attosecond interferometry Walter Pfeiffer 13:25 – 13:45 Attosecond delays in solid state photoemission Armin Feist 13:50 – 14:05 Controlling free-electron wavefunctions by traveling optical waves and whispering-gallery modes Niklas Müller 14:10 – 14:25 Broadband coupling of fast electrons with high-Q whispering gallery mode resonators 14:30 – 15:00 Coffee break Matthias Wollenhaupt 15:00 – 15:20 Dynamic quantum state holography using CEP-stable bichromatic polarization-tailored laser pulses Sajjad Azizi 15:25 – 15:45 Controlling non-adiabatic ionization with ultra-short pulses Matthias Kübel 15:50 – 16:10 Carrier-envelope phase measurements at 3µm wavelength 16:15 – 17:30 Labtours 17:30 – 19:00 Poster session Thursday, 27th February 2020 Fernando Martin 09:00 – 09:35 Attosecond pump-probe spectroscopy of molecular electron dynamics Emil Zak 09:40 – 10:00 Controlling the rotation axis in polyatomic molecules with an optical centrifuge Jochen Mikosch 10:05 – 10:25 Molecular frame studies of channel-resolved laser-driven electron recollision 10:30 – 11:00 Coffee break Philipp Wustelt 11:00 – 11:15 Dissociation of HeH⁺ by long wavelength ultrashort laser pulses Florian Oppermann 11:20 – 11:35 Ionization and dissociation of HeH⁺ in strong two-color fields Adrian Pfeiffer 11:40 – 12:00 Observation of dynamical bloch oscillations in dielectrics Peter Elliott 12:05 – 12:25 Ab-initio transient XMCD spectroscopy 12:30 – 13:25 Lunch break Thursday, 27th February 2020 Alejandro Saenz 13:25 – 14:00 A more detailed look into enhanced ionization in intense laser fields Alexander Kuleff 14:05 – 14:20 Ultrafast non-adiabatic relaxation in XUV-excited molecules Victor Despré 14:25 – 14:40 Ultrafast electron dynamics and its control in the presence of non-adiabatic effects Álvaro Jiménez Gálan 14:45 – 15:05 Lightwave topology for strong-field valleytronics Jin Zhang 15:10 – 15:25 Theoretical investigation of HHG/SHG from hBN rotators Ihar Babushkin 15:30 – 15:45 Ionization dynamics of electrons from the lowest Brunel harmonics 15:50 – 16:20 Coffee break 16:30 – 17:30 Bus transfer – departure at 16:30! 17:30 – 19:30 Excursion – Reichstag 19:30 – 22:00 Dinner at Hackescher Hof 22:00 Bus transfer Friday, 28th February 2020 Markus Gühr 09:00 – 09:35 Photophysics in the gas phase illuminated by ultrafast x-rays and electrons Anne Harth 09:40 – 10:00 Phase information of continuum-continuum couplings Andres Ordonez 10:05 – 10:25 Multiphoton ionization of chiral molecules: what can we control and where's the button to control it? 10:30 – 11:00 Coffee break David Ayuso 11.00 – 11:20 Polarization of chirality Nicolai Klemke 11:25 – 11:40 Circularly polarized high-harmonics from solids originating from intraband dynamics Timo Paschen 11:45 – 12:05 Rescattering effects in two-color photoemission from tungsten needle tips Markus Debatin 12:10 – 12:30 X ray-induced helium nanoplasmas - ultrafast charge migration delays Coulomb explosion 12:35 – 13:30 Lunch break 13:30 – 14:30 Discussion Location map Abstracts Attosecond interferometry Nirit Dudovich One of the most important aspects of attosecond spectroscopy lies in its coherent nature. Resolving the internal coherence is a primary challenge in this field, serving as a key step in our ability to reconstruct the internal dynamics. As in many other branches in physics, coherence is resolved via interferometry. In my talk, I will describe advanced schemes for attosecond interferometry. The application of these schemes provides direct insights into a range of fundamental phenomena in nature, from tunneling and photoionization in atomic systems to ultrafast chiral phenomena in molecules. Attosecond delays in solid state photoemission Walter Pfeiffer S. Neb, A. Gebauer, W. Enns, N. Müller, U. Heinzmann, and W. Pfeiffer E.E. Krasovskii, V. M. Silkin, N. M. Kabachnik, A. K. Kazansky, P. M. Echenique In recent years, time-resolved spectroscopy of electron dynamics in solids advanced to the attosecond regime, i.e. on the time scale on which electron motion occurs on an atomic scale. One example of such a technique is attosecond time- resolved streaking spectroscopy. This technique allows investigating relative temporal delays in the photoemission from different initial states with a resolution down to a few attoseconds. Up to now there is not yet a unified theoretical model for describing the observed photoemission delays in such experiments. In this presentation the present status in the development of such a theoretical model is presented. Based on ab-initio electronic structure calculations, solutions of the time- dependent Schrödinger equation, photoemission delays were determined and are compared to experimentally measured delays for two different materials, i.e., the van-der-Waals crystals WSe2 and BiTeCl. Controlling free-electron wavefunctions by traveling optical waves and whispering-gallery modes Armin Feist In recent years, the manipulation and interaction of electrons with optical fields has seen significant progress, enabling schemes of near-field electron acceleration, attosecond electron pulse generation and capabilities for imaging nano-localized optical modes. Here, we present two novel concepts for the coherent control of free-electron beams in an ultrafast transmission electron microscope (UTEM). In the first experiment, we demonstrate the quantized transfer of photon energy and transverse momentum to a high- coherence electron beam. The three-dimensional optical phase modulation at a laser-illuminated graphite thin film constitutes a coherent inelastic beam splitter for free electrons. In a second study, the phase-matched interaction of electrons with optical whispering gallery modes (WGMs) of dielectric microresonators facilitates a drastically enhanced electron-light coupling and traces the intrinsic temporal cavity ring-down. These results provide for the elementary components of optically programmable electron phase plates and may facilitate a continuous-wave electron acceleration or attosecond structuring by cavity-enhanced and phase-matched optical interactions. Broadband coupling of fast electrons with high-Q whispering-gallery mode resonators Niklas Müller Niklas Müller, Vincent Hock, Christopher Rathje, Holger Koch and Sascha Schäfer The inelastic interaction of fast electrons with spatially confined intense light fields has recently enabled new techniques in ultrafast transmission electron microscopy (UTEM) [1,2,3], enabling the coherent control of free-electron states. Whereas previous work focused on coherent light states as driving fields, advanced quantum control scenarios, including electron-light entanglement and non-trivial electron/photon counting statistics, become accessible if non-classical (quantum optical) light states are applied [4,5,6]. However, to mitigate the reduced coupling strength when considering few-photon-states, novel concepts for coupling electrons to high-Q optical resonators are required. Here, we demonstrate the excitation of high-Q whispering gallery modes in a silica microfiber taper in a transmission electron microscope by relativistic electrons (200 keV electron energy) passing close to the fiber surface. The evanescent electric field of the passing electron induces a femtosecond electric polarization in the silica, which can be decomposed into optical whispering gallery modes (WGM) within the taper geometry. Utilizing a home-built TEM sample holder, fiber- guided light field components are detected in a high-resolution spectrometer. The coherent cathodoluminescence spectra consist of octave-spanning frequency combs with narrow- bandwidth peaks. By probing the WGM resonances for different distances from the taper apex, we demonstrate that the peaks within the comb exhibit a frequency spacing inversely scaling with the local fiber circumference. The experimental results are further supported by simulations of the electron energy loss probability using a transition matrix method [7]. Further it is shown that the bandwidth of the WGM peaks strongly depends on the local taper angle of the fiber, with Q-factors up to 700. [1] De Abajo et al., New J. Phys. 10, 073035 (2008) [2] Barwick et al., Nature 462, 902-906 (2009) [3] Feist et al., Nature 521, 200-203 (2015) [4] Meuret et al., Phys. Rev. Lett. 114, 197401 (2015) [5] Hyun et al., Appl. Phys. Lett. 93, 243106 (2008) [6] Kfir, Phys. Rev. Lett. 123, 103602 (2019) [7] Yalunin et al., Phys. Rev. B 93, 115408 (2016) Dynamic quantum state holography using CEP-stable bichromatic polarization-tailored laser pulses Matthias Wollenhaupt Three-dimensional photoelectron momentum distributions (PMDs) with unusual symmetry properties are generated by multiphoton ionization (MPI) of atoms using polarization- tailored ultrashort laser fields. The PMDs are manipulated by the pulse parameters including the carrier-envelope phase (CEP). In the experiment, we combine supercontinuum pulse shaping with photoelectron tomography for 3D reconstruction of the PMD. A 4f polarization pulse shaper is used to sculpture bichromatic fields from a CEP-stable white light supercontinuum by spectral amplitude and phase modulation [1]. MPI of atoms with single-color sequences