Summary :
The student will develop attosecond spectroscopy techniques making use of the new high reprate Ytterbium laser sources. The ultrafast photoemission dynamics will be studied to reveal in real time the processes of electron scattering/rearrangement as well as electron-ion quantum entanglement, using the charged-particle coincidence techniques.

Detailed summary :
In recent years, there has been spectacular progress in the generation of attosecond (1 as=10-18 s) pulses, rewarded by the 2023 Nobel Prize [1]. These ultrashort pulses are generated from the strong nonlinear interaction of short intense laser pulses with gas jets [2]. A new laser technology based on Ytterbium is emerging, with stability 5 times higher and reprate 10 times higher than the current Titanium:Sapphire technology. These new capabilities represent a revolution for the field.
This opens new prospects for the exploration of matter at the electron intrinsic timescale. Attosecond spectroscopy thus allows studying in real time the quantum process of photoemission, shooting the 3D movie of electronic wavepacket ejection [3,4], and studying quantum decoherence resulting from, e.g., electron-ion entanglement [5].
The first objective of the thesis work is to develop on the ATTOLab laser platform the attosecond spectroscopies using the new Ytterbium laser sources. The second objective is to take advantage of charged particle coincidence techniques, enabled by the high reprate, to study the dynamics of photoemission and quantum entanglement with unprecedented precision.
The student will be trained in ultrafast optics, atomic and molecular physics, quantum optics, and will acquire a broad mastery of XUV and charged-particle spectroscopy techniques.

References :
[1] https://www.nobelprize.org/prizes/physics/2023/summary/
[2] Y. Mairesse, et al., Science 302, 1540 (2003)
[3] V. Gruson, et al., Science 354, 734 (2016)
[4] A. Autuori, et al., Science Advances 8, eabl7594 (2022)
[5] C. Bourassin-Bouchet, et al., Phys. Rev. X 10, 031048 (2020)