Monitoring molecular dynamics using coherent electrons from high harmonic generation Export

@article{PNAS2006NLWagner, abstract = {10.1073/pnas.0605178103 We report a previously undescribed spectroscopic probe that makes use of electrons rescattered during the process of high-order harmonic generation. We excite coherent vibrations in SF using impulsive stimulated Raman scattering with a short laser pulse. A second, more intense laser pulse generates high-order harmonics of the fundamental laser, at wavelengths of ≈20–50 nm. The high-order harmonic yield is observed to oscillate, at frequencies corresponding to all of the Raman-active modes of SF, with an asymmetric mode most visible. The data also show evidence of relaxation dynamics after impulsive excitation of the molecule. Theoretical modeling indicates that the high harmonic yield should be modulated by both Raman and infrared-active vibrational modes. Our results indicate that high harmonic generation is a very sensitive probe of vibrational dynamics and may yield more information simultaneously than conventional ultrafast spectroscopic techniques. Because the de Broglie wavelength of the recolliding electron is on the order of interatomic distances, i.e., ≈1.5 \r{A}, small changes in the shape of the molecule lead to large changes in the high harmonic yield. This work therefore demonstrates a previously undescribed spectroscopic technique for probing ultrafast internal dynamics in molecules and, in particular, on the chemically important ground-state potential surface.}, author = {Wagner, Nicholas L. and W\"{u}est, Andrea and Christov, Ivan P. and Popmintchev, Tenio and Zhou, Xibin and Murnane, Margaret M. and Kapteyn, Henry C.}, citeulike-article-id = {3394383}, citeulike-linkout-0 = {http://dx.doi.org/10.1073/pnas.0605178103}, citeulike-linkout-1 = {http://www.pnas.org/content/103/36/13279.abstract}, citeulike-linkout-2 = {http://www.pnas.org/content/103/36/13279.full.pdf}, citeulike-linkout-3 = {http://view.ncbi.nlm.nih.gov/pubmed/16895984}, citeulike-linkout-4 = {http://www.hubmed.org/display.cgi?uids=16895984}, day = {5}, doi = {10.1073/pnas.0605178103}, journal = {Proceedings of the National Academy of Sciences}, keywords = {coherent, dynamics, electrons, molecular}, number = {36}, pages = {13279--13285}, posted-at = {2008-10-10 20:41:02}, priority = {2}, title = {Monitoring molecular dynamics using coherent electrons from high harmonic generation}, url = {http://dx.doi.org/10.1073/pnas.0605178103}, volume = {103}, year = {2006} }

TY - JOUR ID - PNAS2006NLWagner L3 - citeulike-article-id:3394383 N2 - 10.1073/pnas.0605178103 We report a previously undescribed spectroscopic probe that makes use of electrons rescattered during the process of high-order harmonic generation. We excite coherent vibrations in SF using impulsive stimulated Raman scattering with a short laser pulse. A second, more intense laser pulse generates high-order harmonics of the fundamental laser, at wavelengths of ≈20–50 nm. The high-order harmonic yield is observed to oscillate, at frequencies corresponding to all of the Raman-active modes of SF, with an asymmetric mode most visible. The data also show evidence of relaxation dynamics after impulsive excitation of the molecule. Theoretical modeling indicates that the high harmonic yield should be modulated by both Raman and infrared-active vibrational modes. Our results indicate that high harmonic generation is a very sensitive probe of vibrational dynamics and may yield more information simultaneously than conventional ultrafast spectroscopic techniques. Because the de Broglie wavelength of the recolliding electron is on the order of interatomic distances, i.e., ≈1.5 Å, small changes in the shape of the molecule lead to large changes in the high harmonic yield. This work therefore demonstrates a previously undescribed spectroscopic technique for probing ultrafast internal dynamics in molecules and, in particular, on the chemically important ground-state potential surface. IS - 36 JF - Proceedings of the National Academy of Sciences EP - 13285 TI - Monitoring molecular dynamics using coherent electrons from high harmonic generation VL - 103 SP - 13279 KW - coherent KW - dynamics KW - electrons KW - molecular AU - Wagner, Nicholas AU - Wüest, Andrea AU - Christov, Ivan AU - Popmintchev, Tenio AU - Zhou, Xibin AU - Murnane, Margaret AU - Kapteyn, Henry PY - 2006//05/ UR - http://dx.doi.org/10.1073/pnas.0605178103 ER -