2020-05-21
Attosecond Time-Domain Measurement of Core-Level-Exciton Decay in Magnesium Oxide
Publication
Publication
Phys. Rev. Lett. , Volume 124 - Issue 20 p. 207401: 1- 6
Excitation of ionic solids with extreme ultraviolet pulses creates localized core-level excitons, which in some cases couple strongly to the lattice. Here, core-level-exciton states of magnesium oxide are studied in the time domain at the Mg L2,3 edge with attosecond transient reflectivity spectroscopy. Attosecond pulses trigger the excitation of these short-lived quasiparticles, whose decay is perturbed by time-delayed near-infrared pulses. Combined with a few-state theoretical model, this reveals that the infrared pulse shifts the energy of bright (dipole-allowed) core-level-exciton states as well as induces features arising from dark core-level excitons. We report coherence lifetimes for the two lowest core-level excitons of 2.3±0.2 and 1.6±0.5 fs and show that these are primarily a consequence of strong exciton-phonon coupling, disclosing the drastic influence of structural effects in this ultrafast relaxation process.
Additional Metadata | |
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APS | |
doi.org/10.1103/physrevlett.124.207401 | |
Phys. Rev. Lett. | |
Organisation | High-Harmonic Generation and EUV Science |
Géneaux, R., Kaplan, C., Yue, L., Ross, A., Bækhøj, J., Kraus, P., … Leone, S. (2020). Attosecond Time-Domain Measurement of Core-Level-Exciton Decay in Magnesium Oxide. Phys. Rev. Lett., 124(20), 207401: 1–6. doi:10.1103/physrevlett.124.207401 |