Coherent phase control and quantum interferences in atomic ionization by twocolor laser pulses

D. G. ARBÓ; N. CAMUS; L. FECHNER; S. NAGELE; J. BURGDÖRFER; S. D. LÓPEZ; C. LEMELL; R. MOSHAMMER

Buenos Aires

Simposio; Frontiers in Physica Sciences; 2016

UNSM

Strong-field ionization of atoms with near infra-red laser pulses reveals a rich structure in the momentum distribution of the liberated electron. The patterns observed arise from the interferences of multiple pathways leading to the same final momentum state. They retain precise information about the creation of electron wave-packets in the laser field and the phase they accumulate during the propagation in the combined lase and ionic Coulomb field [1].We show theoretical analysis and experimental results of the ionization process of argon atoms interacting with shaped linearly polarized two-color femtosecond laser pulses. We observe complex asymmetry patterns in the measured three-dimensional momentum distributions.Electron momentum distributions are recorded with a reaction microscope and compared to simulated spectra [2]. By adjusting the relative phase between the red and blue carrier waves, we can control the ionization rate via temporally modified electric field strength. More importantly, this shaped field controls also the trajectories of the ionized electron and the accumulated phase leading to modified interference structures in the three-dimensional momentum distribution [3,4]. We are able to precisely monitor the modifications ofthe interference structures.[1] D. G. Arbó et al., Phys. Rev. A 81, 021403 (2010).[2] D. G. Arbó et al., Phys. Rev. A 92, 023402 (2015).[3] X. Xie et al., Phys. Rev. Lett. 108, 193004 (2012).[4] D. G. Arbó et al., Phys. Rev. A 89 043414 (2014).