Coherence Survival in Resonant Attosecond Ionization Processes

This talk explores through examples the control of coherence in the ionization of atomic and molecular systems by attosecond light pulses. The first example concerns the creation and reconstruction of the electronic coherence of a He⁺ ion following XUV-pump IR-probe ionization of He above the N=2 and N=3 thresholds, where autoionizing states play a prominent role [1,2]. The second example considers the apparent decoherence in integral multiphoton ionization cross sections, when the presence of resonant states cause the radial and angular photoelectron degrees of freedom to be entangled [3]. The third discusses the entanglement between light and matter in the metastable Autler-Townes multiplets that emerge from the interaction between the 3s^-14p and several light-induced states in argon [3,4], which can stabilize resonances against autoionization. A forth example shows how the nuclear recoil due to C-1s photoemission and intramolecular scattering in the CO molecule [5] results in a residual coherence of the ionic vibrational state that can be reconstructed with photoelectron interferometry. This work is supported by the DOE CAREER grant DE-SC0020311 and NSF grant No.1912507.

[1] S Mehmood et al., PRR 3, 023233 (2021).

[2] S Mehmood et al., (submitted - 2023).

[3] D Busto et al., EPJD 76, 112 (2022).

[4] N Harkema et al., PRL 127, 023202 (2021).

[5] S Yanez-Pagans et al., PRA 105, 063107 (2022).

[6] C Cariker et al. (submitted - 2023).

[7] B Ghomashi et al., PRL 127, 203201 (2021).