A5012881284- Spectroscopy and Quantum Chemical Studies
- Laser-Matter Interactions and Applications
- Advanced Chemical Physics Studies
- Spectroscopy and Laser Applications
- Electron and X-Ray Spectroscopy Techniques
- Mass Spectrometry Techniques and Applications
- X-ray Diffraction in Crystallography
- X-ray Spectroscopy and Fluorescence Analysis
- Photochemistry and Electron Transfer Studies
University of California, Berkeley
2020-2024
Lawrence Berkeley National Laboratory
2020-2023
Berkeley College
2020
Nonlinear wave mixing in solids with ultrafast x-rays can provide insight into complex electronic dynamics of materials. Here, tabletop-based attosecond noncollinear four-wave (FWM) spectroscopy using one extreme ultraviolet (XUV) pulse from high harmonic generation and two separately timed few-cycle near-infrared (NIR) pulses characterizes the ${\mathrm{Na}}^{+}$ ${L}_{2,3}$ edge core-excitons NaCl around 33.5 eV. An inhomogeneous distribution underlying well-known doublet absorption...
Attosecond four-wave mixing spectroscopy using an XUV pulse and two noncollinear near-infrared pulses is employed to measure Rydberg wavepacket dynamics resulting from extreme ultraviolet excitation of a 3s electron in atomic argon into series autoionizing 3s-1np states around 29 eV. The emitted signals individual exhibit oscillatory structure persist well beyond the expected lifetimes emitting states. These results reflect substantial contributions longer-lived four wave emission each...
Attosecond XUV wave-mixing spectroscopy probes the few-fs decay dynamics of short-lived 3sσ<sub>g</sub> Rydberg state O<sub>2</sub>.
<title>Abstract</title> Photoinduced biological and chemical reactions are often based on key structural transformations of a molecule driven across multiple electronic states. Acetylacetone (AcAc) is prototypical system for complex pathways involving several conical intersections (CI) singlet-triplet intersystem crossings (ISC) characterized by distinct geometries. In the gas phase, AcAc predominantly in planar ring-like enolic form stabilized strong intramolecular O-H∙∙∙O hydrogen bond....
Attosecond noncollinear four-wave-mixing spectroscopy with one attosecond extreme ultraviolet (XUV) pulse and two few-cycle near-infrared (NIR) pulses was used to measure the autoionization decay lifetimes of inner valence electronic excitations in neon atoms. After a 43--48-eV XUV photon excites $2s$ electron into $2s2{p}^{6}\phantom{\rule{0.16em}{0ex}}(np)$ Rydberg series, broadband NIR couple $2s2{p}^{6}3p$ XUV-bright state neighboring $2s2{p}^{6}3s$ $2s2{p}^{6}3d$ XUV-dark states....
Nonlinear spectroscopies can disentangle spectra that are congested due to inhomogeneous broadening. In conjunction with theoretical calculations, attosecond extreme ultraviolet (XUV) four-wave-mixing (FWM) spectroscopy is utilized here probe the dynamics of autoionizing inner valence excited Rydberg states polyatomic molecule, ${\mathrm{CO}}_{2}$. This tabletop nonlinear technique employs a short XUV pulse train and two noncollinear, few-cycle near-infrared pulses generate background-free...
Multiple Rydberg series converging to the O 2 + 𝑐 4 Σ 𝑢 − state, accessed by 20-25 eV extreme ultraviolet (XUV) light, serve as important model systems for competition between nuclear dissociation and electronic autoionization. The dynamics of lowest member these series, 3sσg state around 21 eV, has been challenging study owing its ultra-short lifetime (< 10 fs). Here, we apply transient wave-mixing spectroscopy with an attosecond XUV pulse investigate decay this state. Lifetimes 5.8±0.5...
Nonlinear spectroscopies can disentangle spectra that are congested due to inhomogeneous broadening. In conjunction with theoretical calculations, attosecond extreme ultraviolet (XUV) four-wave mixing (FWM) spectroscopy is utilized here probe the dynamics of autoionizing, inner valence excited Rydberg states polyatomic molecule, CO2. This tabletop nonlinear technique employs a short XUV pulse train and two noncollinear, few-cycle near infrared pulses generate background-free wave-mixing...