Proc Natl Acad Sci U S A
April 2019
Structural information on electronically excited neutral molecules can be indirectly retrieved, largely through pump-probe and rotational spectroscopy measurements with the aid of calculations. Here, we demonstrate the direct structural retrieval of neutral carbonyl disulfide (CS) in the [Formula: see text] excited electronic state using laser-induced electron diffraction (LIED). We unambiguously identify the ultrafast symmetric stretching and bending of the field-dressed neutral CS molecule with combined picometer and attosecond resolution using intrapulse pump-probe excitation and measurement.
View Article and Find Full Text PDFLaser-induced electron diffraction is an evolving tabletop method that aims to image ultrafast structural changes in gas-phase polyatomic molecules with sub-Ångström spatial and femtosecond temporal resolutions. Here we demonstrate the retrieval of multiple bond lengths from a polyatomic molecule by simultaneously measuring the C-C and C-H bond lengths in aligned acetylene. Our approach takes the method beyond the hitherto achieved imaging of simple diatomic molecules and is based on the combination of a 160 kHz mid-infrared few-cycle laser source with full three-dimensional electron-ion coincidence detection.
View Article and Find Full Text PDFWe report 32% efficient frequency doubling of single-frequency 1029 nm light to green light at 514.5 nm using a single-pass configuration. A congruent composition, periodically poled magnesium-doped lithium niobate (PPMgLN) crystal of 50 mm length was used to generate a second-harmonic power of 2.
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