Article
Multidisciplinary Sciences
Andrew S. Maxwell, Lars Bojer Madsen, Maciej Lewenstein
Summary: The study explores the possibility of orbital angular momentum (OAM) entanglement in attosecond imaging and investigates the entanglement properties of photoelectrons in non-sequential double ionization. Through calculations of logarithmic negativity and entanglement witness, the study reveals the robustness of entanglement to incoherence and the relationship between OAM coherence terms and entanglement measurement. The entanglement of photoelectron pairs with the highest degree of entanglement is quantified for various targets and field parameters. This methodology provides a universal approach to quantify and measure entanglement using OAM, which is well-suited for attosecond processes and can enhance imaging capabilities or generate OAM-entangled electrons.
NATURE COMMUNICATIONS
(2022)
Article
Physics, Multidisciplinary
Xiaomeng Ma, Xiaofan Zhang, Aihong Tong
Summary: Using a three-dimensional semi-classical ensemble model, we investigated non-sequential double ionization induced by orthogonal two-color laser pulses. Our calculations demonstrate that the proportion of events with multiple returnings, the total energy of the two electrons, and the ion momentum distribution are all influenced by the relative phase of the two-color fields, exhibiting periodic oscillations with a period of p. By analyzing the trajectories, we found that the recollision energy of the electron can be controlled by changing the relative phase of the two-color laser pulse, resulting in phase-dependent ion momentum distributions. Additionally, the ion momentum distribution for multiple-returning events is wider compared to single-returning cases due to the binary recollision leading to a smaller scattering angle of the first electron.
FRONTIERS IN PHYSICS
(2023)
Article
Optics
Jingkun Xu, Jintai Liang, Xiaomeng Ma, Kunlong Liu, Yingbin Li, Chuanpeng Cao, Min Li, Benhai Yu, Yueming Zhou, Peixiang Lu
Summary: The nondipole effect in strong-field sequential double ionization of an Ar atom is investigated using a classical ensemble model, and it is found that the magnetic field induces significant displacement of the electron, which affects the electron-ion rescattering.
Article
Multidisciplinary Sciences
Do Hyung Kang, Jinwoo Kim, Heung-Ryoul Noh, Sang Kyu Kim
Summary: The ponderomotive effect in non-valence bound states of molecular anions has been experimentally demonstrated for the first time, showing clear-cut blue-shifts in quantum levels under the influence of a non-resonant picosecond control laser pulse. This suggests potential for manipulating polyatomic molecules using the dynamic Stark effect.
NATURE COMMUNICATIONS
(2021)
Article
Physics, Multidisciplinary
H. Jiang, M. Mandrysz, A. Sanchez, J. Dura, T. Steinle, J. S. Prauzner-Bechcicki, J. Zakrzewski, M. Lewenstein, F. He, J. Biegert, M. F. Ciappina
Summary: This study investigates the non-sequential double ionization (NSDI) in argon induced by a 3100 nm laser source through joint experimental and theoretical approaches. The correlated photoelectron momentum distribution (PMD) is found to strongly depend on the pulse duration, which can be explained by an envelope-induced intensity effect. The laser vector potential at the ionization time of the bound electron is influenced by the pulse duration, leading to different drift momenta. This work highlights the significance of pulse duration in NSDI and enhances our understanding of strong field tunnel-recollision dynamics under mid-IR laser fields.
NEW JOURNAL OF PHYSICS
(2023)
Article
Biochemistry & Molecular Biology
Ana I. Lozano, Filipe Costa, Xueguang Ren, Alexander Dorn, Lidia Alvarez, Francisco Blanco, Paulo Limao-Vieira, Gustavo Garcia
Summary: This paper presents experimental results for the electron impact ionization of benzene, providing double and triple differential cross sections at an incident energy of 90 eV. The most intense ionization channel is associated with the formation of the parent ion. The study also derives a semi-empirical formula for inelastic angular distribution function in electron transport simulations based on the DDCS results.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2021)
Article
Physics, Multidisciplinary
Pei-Lun He, Karen Z. Hatsagortsyan, Christoph H. Keitel
Summary: We investigate the ion momentum distribution in the x-ray-induced dissociative photoionization of molecules by analyzing the ionization under the Born-Oppenheimer approximation and simulating the ion motion using the Schrodinger equation. The entanglement between the ion and photoelectron transfers information of electronic interference to the ion dynamics, resulting in Young's double-slit interference patterns in the ion momentum distributions of dissociative molecular photoionization. We demonstrate that even when the correlated photoelectron information is lost, double-slit interference signatures still persist in the ion longitudinal momentum shift in the case of heteronuclear molecules.
PHYSICAL REVIEW LETTERS
(2023)
Article
Biochemical Research Methods
Viviane Morcelle, Aline Medina, Leonardo C. Ribeiro, Italo Prazeres, Ricardo R. T. Marinho, Manuela S. Arruda, Luis A. Mendes, Mabele de Jesus Santos, Antonio Carlos Fontes dos Santos
Summary: This study examined the single-photon double ionization of the SUVA 134a molecule and found that the process can be expressed as a combination of shake-off and knockout processes. Experimental data supported by models show similarities in behavior with other atomic and molecular systems. The lower double-to-total photoionization fraction of SUVA compared to other systems may be attributed to its larger volume and lower electron density.
RAPID COMMUNICATIONS IN MASS SPECTROMETRY
(2021)
Article
Multidisciplinary Sciences
Philipp Geppert, Max Althoen, Daniel Fichtner, Herwig Ott
Summary: Exploring the dynamics of inelastic and reactive collisions on the quantum level is a fundamental goal in quantum chemistry. Such collisions are of particular importance in connection with Rydberg atoms in dense environments since they may considerably influence both the lifetime and the quantum state of the scattered Rydberg atoms. The authors report on the study of state-changing collisions between Rydberg atoms and ground state atoms, finding that the outcome of such collisions is not limited to a single hydrogenic manifold, and observing a redistribution of population over a wide range of final states. They also find that even the decay to states with the same angular momentum quantum number as the initial state, but different principal quantum number is possible.
NATURE COMMUNICATIONS
(2021)
Article
Physics, Multidisciplinary
Yu-Hao Zhu
Summary: The direct double ionization of H2 and N2 molecules induced by electron-impact is investigated theoretically. Our approach can obtain the cross section of each ionization channel, which is helpful to understanding the ionization competition mechanism of small homo-nuclear diatomic molecules.
Article
Physics, Applied
K. Grosse, M. Falke, A. von Keudell
Summary: This paper examines nanosecond plasmas in water created by applying positive and negative polarity to a sharp tungsten electrode. It is found that plasma ignition is dominated by field effects at the electrode-liquid interface, resulting in higher surface temperature and electron density for positive polarity compared to negative polarity.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Engineering, Electrical & Electronic
Junya Yaita, Koichi Fukuda, Atsushi Yamada, Takuya Iwasaki, Shu Nakaharai, Junji Kotani
Summary: The study identified the primary reason for the reduced electron mobility in QW GaN-HEMT and proposed a solution to alleviate the electric field and increase electron mobility. As a result, the electron mobility of the QW GaN-HEMT structure was significantly improved.
IEEE ELECTRON DEVICE LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Shradha Gupta, Janesh K. Kaushik, Ankur Gupta
Summary: A physical model is proposed to explain the breakdown of the virtual gate region and the complex contour of kink in AlGaN/GaN HEMTs output I-V characteristics, taking into account the impact ionization and multiphonon assisted ionization of surface traps.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Physics, Fluids & Plasmas
S. Eliseev
Summary: This paper presents a simple analytical model for short direct-current glow discharge in narrow discharge tubes, taking into account the influence of radial losses of charged particles due to ambipolar diffusion. The model is based on the analytical parameterization of non-local ionization produced by fast electrons, allowing for an exact solution of the ambipolar diffusion equation with radial particle losses.
PHYSICS OF PLASMAS
(2022)
Article
Chemistry, Physical
Dan Wu, Qingyi Li, Jun Wang, Fuming Guo, Jigen Chen, Yujun Yang
Summary: The study reveals that the double ionization of hydrogen molecules in high-intensity laser pulses is mainly controlled by sequential double ionization, and the correlation behavior of electron momenta is related to the variation of nuclear distance. The electron momentum correlation depends on the laser pulse's negative vector potential, corresponding to the ionization instants of the two electrons.
CHEMICAL PHYSICS LETTERS
(2021)
Article
Physics, Multidisciplinary
Laura Cattaneo, Luca Pedrelli, Roger Y. Bello, Alicia Palacios, Phillip D. Keathley, Fernando Martin, Ursula Keller
Summary: This letter investigates the impact of nuclear motion on the measurement of electronic dynamics using two popular attosecond techniques. The results show that streaking is a better choice for isolating attosecond electron dynamics.
PHYSICAL REVIEW LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Jonas Heidrich, Marco Gaulke, Matthias Golling, Behcet Ozgur Alaydin, Ajanta Barh, Ursula Keller
Summary: This study presents the first modelocked backside-cooled GaSb VECSEL operating above 2 μm. By using a two quantum well InGaSb SESAM in a V-shaped cavity arrangement, femtosecond and picosecond mode-locking were achieved, and the performance and intracavity group delay dispersion of the laser were investigated.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2022)
Article
Optics
C. P. Bauer, S. L. Camenzind, J. Pupeikis, B. Willenberg, C. R. Phillips, U. Keller
Summary: We demonstrate a free-running single-cavity dual-comb optical parametric oscillator (OPO) pumped by a single-cavity dual-comb solid-state laser. The OPO generates high-power idler and signal beams with narrow linewidth and low noise, making it suitable for sensitive mid-infrared dual-comb spectroscopy applications.
Article
Optics
Sergei Tomilov, Yicheng Wang, Martin Hoffmann, Jonas Heidrich, Matthias Golling, Ursula Keller, Clara J. Saraceno
Summary: In this study, semiconductor saturable absorber mirror (SESAM) modelocked Ho:YAG thin-disk lasers emitting at 2.1-mu m achieved record-holding performance levels with 50W of average power, 1.13-ps pulses, 2.11 mu J of pulse energy, and around 1.9 MW of peak power. The highest output pulse energy and average power demonstrated so far in the 2-mu m wavelength region from a modelocked laser.
Article
Optics
Jie Zhou, Xu Wang
Summary: We propose a method to construct stable classical multielectron model atoms with ionization energies optimized to match experimental values. Utilizing auxiliary potentials to simulate quantum mechanical effects introduced in the work of Kirschbaum and Wilets [Phys. Rev. A 21, 834 (1980)], we employ a genetic algorithm to optimize the relevant parameters and ensure that the model atoms produce correct (first few) ionization energies. Optimized model atoms with ionization energies automatically exhibit distinct electron shells, consistent with conventional expectations. Numerical examples are provided to highlight the importance of accurate ionization energies and offer new insights into double ionization processes.
Article
Physics, Multidisciplinary
Kang Lin, Xiang Chen, Sebastian Eckart, Hui Jiang, Alexander Hartung, Daniel Trabert, Kilian Fehre, Jonas Rist, Lothar Ph H. Schmidt, Markus S. Schoeffler, Till Jahnke, Maksim Kunitski, Feng He, Reinhard Doerner
Summary: The magnetic component of the driving electromagnetic field plays an important role in nonsequential double ionization, but does not affect the forward shift of the electrons.
PHYSICAL REVIEW LETTERS
(2022)
Article
Multidisciplinary Sciences
Kang Lin, Sebastian Eckart, Alexander Hartung, Daniel Trabert, Kilian Fehre, Jonas Rist, Lothar Ph H. Schmidt, Markus S. Schoeffler, Till Jahnke, Maksim Kunitski, Reinhard Doerner
Summary: In the photoelectric effect, the energy of electrons is affected by their emission direction, with photoelectrons emitted against the light propagation direction shifting to higher values and those emitted along the light propagation direction shifting to lower values. This energy shift is attributed to a non-dipole contribution to the ponderomotive potential resulting from the interaction of moving electrons with incident photons.
Article
Multidisciplinary Sciences
Travis Severt, Zachary L. Streeter, Wael Iskandar, Kirk A. Larsen, Averell Gatton, Daniel Trabert, Bethany Jochim, Brandon Griffin, Elio G. Champenois, Matthew M. Brister, Dylan Reedy, Demitri Call, Richard Strom, Allen L. Landers, Reinhard Doerner, Joshua B. Williams, Daniel S. Slaughter, Robert R. Lucchese, Thorsten Weber, C. William McCurdy, Itzik Ben-Itzhak
Summary: In this study, the authors successfully separate the sequential breakup pathways in the double ionization of water molecules and experimentally identify, separate, and sequentially track the two fragmentation paths of the intermediate OD+ ion. Determining the time evolution of reactions at the quantum mechanical level is crucial for understanding molecular dynamics.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Lianrong Zhou, Hongcheng Ni, Zhejun Jiang, Junjie Qiang, Wenyu Jiang, Wenbin Zhang, Peifen Lu, Jin Wen, Kang Lin, Meifang Zhu, Reinhard Doerner, Jian Wu
Summary: The formation of trihydrogen cation driven by light has been of great interest due to its important role in initiating chemical reactions in interstellar clouds. Previous studies focused on the formation of H-3(+) or D-3(+) from unimolecular reactions, but we observed and characterized the ultrafast formation of D-3(+) from a bimolecular reaction. Molecular dynamics simulations provided an intuitive representation of the reaction dynamics, which matched well with experimental observations. Additionally, we demonstrated control over the emission direction of D-3(+) using a tailored two-colour femtosecond laser field, based on the mechanism known for light control of electron localization in single molecules.
Article
Physics, Multidisciplinary
D. Trabert, N. Anders, A. Geyer, M. Hofmann, M. S. Schoeffler, L. Ph. H. Schmidt, T. Jahnke, M. Kunitski, R. Doerner, S. Eckart
Summary: We experimentally studied the strong-field ionization of the argon dimer in a co-rotating two-color laser field. A subcycle interference pattern in the photoelectron momentum distribution was observed, and the Wigner time delay was inferred using holographic angular streaking of electrons. It was found that the Wigner time delay varied by more than 400 attoseconds with respect to the electron emission direction relative to the molecular axis. The measured time delay was independent of the parity of the dimercation and agreed well with the theoretical model based on the ionization of an aligned atomic p orbital.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Physics, Multidisciplinary
G. Nalin, N. M. Novikovskiy, K. Fehre, N. Anders, D. Trabert, S. Grundmann, M. Kircher, A. Khan, R. Tomar, M. Hofmann, M. Waitz, I. Vela-Perez, G. Kastirke, J. Siebert, D. Tsitsonis, C. Kuestner-Wetekam, L. Marder, J. Viehmann, F. Trinter, H. Fukuzawa, K. Ueda, J. B. Williams, A. Knie, R. Doerner, M. S. Schoeffler, T. Jahnke, Ph. V. Demekhin
Summary: We experimentally and theoretically studied the differential photoelectron circular dichroism (PECD) of O 1s photoelectrons of R-trifluoromethyloxirane enantiomers with different photoelectron kinetic energies. By using cold target recoil ion momentum spectroscopy, we detected the photoelectrons and two ionic molecular fragments simultaneously, enabling determination of the molecule's orientation in the laboratory frame and obtaining molecular-frame photo-electron diffraction patterns for deducing the differential PECD. The observed normalized PECD strength clearly exceeds 50% for given molecular orientations and photoelectron emission directions, consistent with relaxed-core Hartree-Fock calculations using the single center method. These results support our recent discovery of a significant differential PECD in O 1s photoemission of the methyloxirane molecule.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Physics, Multidisciplinary
Andreas Hans, Florian Trinter, Philipp Schmidt, Sebastian Eckart, Sven Grundmann, Gregor Hartmann, Xaver Holzapfel, Carolin Honisch, Gregor Kastirke, Max Kircher, Niklas Melzer, Christian Ozga, Clemens Richter, Jonas Rist, Markus Schoeffler, Daniel Trabert, Isabel Vela-Perez, Johannes H. Viehmann, Miriam Weller, Reinhard Doerner, Uwe Hergenhahn, Arno Ehresmann, Andre Knie, Kirill Gokhberg, Aryya Ghosh, Till Jahnke
Summary: The role of interatomic and intermolecular energy and charge-transfer processes in weakly bound matter is currently debated. Two mechanisms of single-photon two-site double ionization in Ne dimers and clusters are discussed, occurring competitively or subsequently to resonant interatomic Coulombic decay (rICD). The first mechanism is photoelectron-impact ionization, enhanced by resonant excitation. The second mechanism is collisional ionization of energetic Rydberg atoms produced by rICD in Ne clusters and ionized by collisions with neutrals.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Physics, Multidisciplinary
Mouli Hazra, Pallabi Paul, Doyeong Kim, Christin David, Stefanie Graefe, Ulf Peschel, Matthias Kuebel, Adriana Szeghalmi, Adrian N. Pfeiffer
Summary: Introduced a method called nonlinear polarization holography for retrieving the time-domain nonlinear response of metal films, allowing the distinction between excitation and relaxation mechanisms of low-energy electrons using subcycle precision.
NEW JOURNAL OF PHYSICS
(2023)
Article
Optics
Jie Zhou, Bradford K. Talbert, Yu Hang Lai, Sha Li, Cosmin Blaga, Pierre Agostini, Xu Wang, Louis F. DiMauro
Summary: Research has shown that atomic magnesium ionizes more efficiently in 400-nm laser fields with circular polarization compared to linear polarization. This result is qualitatively reproduced through numerical solutions of a two-electron time-dependent Schrödinger equation. Theoretical analysis reveals the crucial role of intermediate excited states during the ionization process. The 3s3p state and the 3s3d state are identified as the dominant intermediate states, with the main ionization pathway being 3s2 -* 3s3p -* 3s3d -* ionized states. Circularly polarized laser fields are found to pump more population from the ground state to the 3s3d state, leading to more efficient ionization of magnesium atoms.
Article
Optics
X. Li, A. Rudenko, T. Mazza, A. Roerig, N. Anders, Th. M. Baumann, S. Eckart, B. Erk, A. De Fanis, K. Fehre, R. Doerner, L. Foucar, S. Grundmann, P. Grychtol, A. Hartung, M. Hofmann, M. Ilchen, Ch. Janke, G. Kastirke, M. Kircher, K. Kubicek, M. Kunitski, S. Meister, N. Melzer, J. Montano, V. Music, G. Nalin, Y. Ovcharenko, Ch. Passow, A. Pier, N. Rennhack, J. Rist, D. E. Rivas, I. Schlichting, L. Ph. H. Schmidt, Ph. Schmidt, M. S. Schoeffler, J. Siebert, N. Strenger, D. Trabert, F. Trinter, I Vela-Perez, R. Wagner, P. Walter, M. Weller, P. Ziolkowski, A. Czasch, M. Meyer, T. Jahnke, D. Rolles, R. Boll
Summary: This study reports on the observation of resonance effects in molecule CH3I induced by intense x-ray pulses, leading to photon-energy-dependent shift of resonance-induced structures in ion charge state distributions. By comparing the ion charge state distribution of CH3I with that from ionization of atomic xenon, molecule-specific features attributed to ultrafast intramolecular charge rearrangement were observed. Additionally, the study experimentally demonstrates that charge-rearrangement-enhanced x-ray ionization of molecules also plays a role in the soft x-ray regime, previously identified with hard x rays.
