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arXiv:2108.03270 · Physical Review A

Magnetic dichroism in few-photon ionization of polarized atoms

B. P. Acharya, M. Dodson, Santwana Dubey, K. L. Romans, A. H. N. C. De Silva, K. Foster, O. Russ, Klaus Bartschat, Nicolas Douguet, D. Fischer

Published Nov 5, 2021• 16 citations
arXivHTMLPDF

Abstract

We consider few-photon ionization of atomic lithium by linearly polarized femtosecond laser pulses and demonstrate that asymmetries of the electron angular distribution can occur for initially polarized $(2p,$ $m$=$+1)$ target atoms. The dependence of the photoelectron emission angle relative to the electric field direction is investigated at different laser intensities and wavelengths. The experimental spectra show excellent agreement with numerical solutions of the time-dependent Schr\"odinger equation. In the perturbative picture, the angular shift is traced back to interferences between partial waves with mean magnetic quantum number $\ensuremath{\langle}m\ensuremath{\rangle}\ensuremath{\ne}0$. This observation allows us to obtain quantum mechanical information on the final electronic state.

DOI
10.1103/physreva.104.053103

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