A5032871790- Laser-Matter Interactions and Applications
- Atomic and Molecular Physics
- Mass Spectrometry Techniques and Applications
- Advanced Chemical Physics Studies
- Spectroscopy and Quantum Chemical Studies
- Advanced Fiber Laser Technologies
- Laser-Plasma Interactions and Diagnostics
- Laser-induced spectroscopy and plasma
- Laser Design and Applications
- Cold Atom Physics and Bose-Einstein Condensates
- X-ray Spectroscopy and Fluorescence Analysis
- Electron and X-Ray Spectroscopy Techniques
- Quantum, superfluid, helium dynamics
- Particle accelerators and beam dynamics
- Ion-surface interactions and analysis
- Quantum optics and atomic interactions
- Spectroscopy and Laser Applications
- Nuclear physics research studies
- Quantum chaos and dynamical systems
- Atomic and Subatomic Physics Research
- Quantum Mechanics and Applications
- Photochemistry and Electron Transfer Studies
- Terahertz technology and applications
- Molecular Junctions and Nanostructures
- Laser Material Processing Techniques
University of Tsukuba
2015-2025
Hangzhou First People's Hospital
2025
Shanxi Medical University
2022-2025
Wuxi Fourth People's Hospital
2025
First Affiliated Hospital of Wenzhou Medical University
2025
ETH Zurich
2018
Lawrence Berkeley National Laboratory
2018
First Affiliated Hospital Zhejiang University
2015
TU Wien
2001-2013
Northwestern Polytechnical University
2008-2010
We have extended the tunneling ionization model of Ammosov-Delone-Krainov (ADK) for atoms to diatomic molecules by considering symmetry property and asymptotic behavior molecular electronic wave function. The structure parameters several needed calculating rates using this ADK been obtained. theory is applied calculate ratios signals with their companion that nearly identical binding energies. origin suppression some has identified. predicted pairs $({\mathrm{D}}_{2}:\mathrm{Ar},$...
We propose an empirical formula for the static field ionization rates of atoms and molecules by extending well-known analytical tunnelling to barrier-suppression regime. The validity this is checked against calculated from solving Schrödinger equation a number ions. retains simplicity original rate expression but can be used calculate lasers at high intensities.
High-order-harmonic generation by a highly nonlinear interaction of infrared laser fields with matter allows for the attosecond pulses in XUV spectral regime. This process, well established atoms, has been recently extended to condensed phase. Remarkably well-pronounced harmonics up order $\ensuremath{\sim}30$ have observed dielectrics. We establish route toward an ab initio multiscale simulation solid-state high-order-harmonic generation. find that mesoscopic effects system, particular...
We present an ab initio three-dimensional quantum study of high-order harmonic generation (HHG) atomic H in intense pulsed laser fields. Accurate time-dependent wave functions are obtained by means the generalized pseudospectral method recently developed and wavelet transform is used to perform time-frequency analysis resulting HHG power spectra. The results reveal striking details spectral temporal fine structures HHG, providing insights regarding mechanisms different energy regimes...
The direct observation of molecular dynamics initiated by x-rays has been hindered to date the lack bright femtosecond sources short-wavelength light. We used soft x-ray beams generated high-harmonic upconversion a laser photoionize nitrogen molecule, creating highly excited cations. A strong infrared pulse was then probe ultrafast electronic and nuclear as molecule exploded. found that substantial fragmentation occurs through an electron-shakeup process, in which second electron is...
We demonstrate that the structure of outermost orbitals oxygen and nitrogen can be observed in angular distribution coincident ion pairs generated by double ionization these molecules 8 fs laser pulses. do this establishing ions emerge from well defined excited electronic states O2+2 N2+2 respectively they are produced dominantly through a process which involves electron rescattering. The distributions two targets very different, reflecting different structures molecules.
Using a simple model of strong-field ionization atoms that generalizes the well-known 3-step from 1D to 3D, we show experimental photoelectron angular distributions resulting laser xenon and argon display prominent structures correspond electrons pass by their parent ion more than once before strongly scattering. The shape these can be associated with specific number times electron is driven past its in field Furthermore, careful analysis cutoff energy allows us experimentally measure...
We have studied the carrier-envelope phase-dependent above-threshold-ionization processes by solving time-dependent Schr\"odinger equation nonperturbatively. Our simulated spectra are in good agreement with experimental measurement of Paulus et al. [Phys. Rev. Lett. 91, 253004 (2003)] if we shift phase $0.15\ensuremath{\pi}$. This means that recalibrated more accurately comparing our simulations measurements. Furthermore, tracing back origin ionized electrons, clearly identified low-energy...
Strong-field ionization provides fundamental insight into light-matter interactions, encoding the structure of atoms and molecules on sub\aa{}ngstr\"om subfemtosecond scales. In this Rapid Communication, we explore an important regime: strong-field by two-color circularly polarized laser fields. contrast to past work using linearly drivers, probe electron trajectories that are driven in a two-dimensional plane, thus separating tunneling angle from rescattering angle. This allows us make...
High harmonic light sources make it possible to access attosecond time-scales, thus opening up the prospect of manipulating electronic wave packets for steering molecular dynamics. However, two decades after birth physics, concept chemistry has not yet been realized. This is because excitation and manipulation orbitals requires precisely controlled waveforms in deep ultraviolet, which have synthesized. Here, we present a novel approach using vacuum ultraviolet pulse-trains coherently excite...
We theoretically investigate the generation of ultrafast currents in insulators induced by strong few-cycle laser pulses. Ab initio simulations based on time-dependent density functional theory give insight into atomic-scale properties current signifying a femtosecond-scale insulator-metal transition. observe transition from nonlinear polarization during pulse at low intensities to tunnelinglike excitation conduction band higher intensities. At high intensities, persists after conclusion...
Strong-field ionization in two-color circularly polarized fields is studied, where both experimental measurements and theoretical analyses suggest that the production of high-energy electrons from electron-ion rescattering optimized counterrotating fields, when ponderomotive energies two laser are equal.
We present a self-interaction-free density-functional theory (DFT) for the treatment of both static properties ground states and photoionization processes many-electron systems. The method is based on Krieger-Li-Iafrate (KLI) optimized effective potential (OEP) incorporation an explicit self-interaction correction (SIC) term. Such extended OEP--KLI-SIC uses only orbital-independent single-particle local potentials thus computationally more efficient yet maintains good accuracy. usefulness...
We have measured coincident ion pairs produced in the Coulomb explosion of H2 by 8-30 fs laser pulses at different intensities. show how can be experimentally controlled tuning appropriate pulse duration and intensity. For less than 15 fs, we found that rescattering-induced is dominated first-return recollisions, while for longer proper intensity, third return made to major one. Additionally, choosing suitable proceeding through three distinct processes are simultaneously observable, each...
We exploit a method to precisely calibrate the peak intensity of intense laser pulses by measuring momentum transferred ion in single ionization circularly polarized light. Using this approach, we show how experimental data can be used get information about absolute rate at specific local laser-peak within focal volume. The results are compared other obtained with different methods laser-peak-intensity calibration described literature.
We present a self-interaction-free time-dependent density-functional theory (TDDFT) for nonperturbative treatment of multiphoton processes many-electron atomic systems in intense laser fields. The is based on the extension Kohn-Sham formalism. exchange-correlation potential with proper short- and long-range behavior constructed by means optimized effective (TDOEP) method incorporation an explicit self-interaction correction (SIC) term. resulting TDOEP-SIC equations are structurally similar...
We present ab initio quantum and classical investigations on the production control of a single attosecond pulse by using few-cycle intense laser pulses as driving field. The high-harmonic-generation power spectrum is calculated accurately efficiently solving time-dependent Schr\"odinger equation generalized pseudospectral method. time-frequency characteristics xuv are analyzed in detail means wavelet transform induced dipole. To better understand physical processes, we also perform...
Two-dimensional (2D) electron momentum distributions and energy spectra for multiphoton ionization of atoms by intense laser pulses, calculated solving the time-dependent Schr\"odinger equation (TDSE) different wavelengths intensities, are compared to those predicted strong-field approximation (SFA). It is shown that at low energies between TDSE SFA quite differences arise largely from absence a long-range Coulomb interaction in SFA. We further found low-energy 2D exhibit ubiquitous fanlike...
We report the experimentally determined angular distribution of $[1s2{s}^{2}2{p}_{1/2}{]}_{1}\ensuremath{\rightarrow}[1{s}^{2}2{s}^{2}{]}_{0}$ transition in dielectronic recombination Li-like Au. Recently, Fritzsche et al. [Phys. Rev. Lett. 103, 113001 (2009)] predicted that Breit interaction plays a dominant role this transition. However, phenomenon has not yet been observed due to technical difficulties conventional methods. To overcome difficulties, we combine two different measurements...
Atomic ionization by intense mid-infrared (mid-IR) pulses produces low electron energy features that the strong-field approximation, which is expected to be valid in tunneling regime characterized small Keldysh parameters ($\gamma \ll 1$), cannot describe. These include low-energy structure (LES), very-low-energy (VLES), and more recently found zero-energy (ZES). They result from interplay between laser electric field atomic Coulomb controls spectrum also for $\gamma$. In present joint...
We studied the elementary processes of excitation and ionization atomic hydrogen in an intense 800-nm pulse with intensity 1.0 to $2.5\ifmmode\times\else\texttimes\fi{}{10}^{14}$ ${\mathrm{W}/\mathrm{cm}}^{2}$ range. By analyzing as a continuation above-threshold (ATI) into below-threshold negative energy region, we show that modulation probability well-known shift low-energy ATI peaks vs laser share same origin. Modulation is general strong field phenomenon shown be consequence channel...
Abstract We publish three Roadmaps on photonic, electronic and atomic collision physics in order to celebrate the 60th anniversary of ICPEAC conference. In Roadmap I, we focus light–matter interaction. this area, studies ultrafast molecular dynamics have been rapidly growing, with advent new light sources such as attosecond lasers x-ray free electron lasers. parallel, experiments established synchrotron radiation femtosecond using cutting-edge detection schemes are revealing scientific...
Interaction of a strong laser pulse with matter transfers not only energy but also linear momentum the photons. Recent experimental advances have made it possible to detect small amount delivered photoelectrons in strong-field ionization atoms. We present numerical simulations as well an analytical description subcycle phase (or time) resolved transfer atom accessible by attoclock protocol. show that light-field-induced is remarkably sensitive properties ultrashort such its carrier-envelope...