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arXiv · 1808.01860

Maximum Elliptical Dichroism in Atomic Two-Photon Ionization

J. Hofbrucker·A. V. Volotka·S. Fritzsche
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Abstract

Elliptical dichroism is known in atomic photoionization as the difference in the photoelectron angular distributions produced in nonlinear ionization of atoms by left- and right-handed elliptically polarized light. We theoretically demonstrate that the maximum dichroism |{\Delta}_{ED}|=1 always appears in two-photon ionization of any atom if the photon energy is tuned in so that the electron emission is dominantly determined by two intermediate resonances. We propose the two-photon ionization of atomic helium in order to demonstrate this remarkable phenomenon. The maximum elliptical dichroism could be used as a sensitive tool for analyzing the polarization state of photon beams produced by free-electron lasers.

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J. Hofbrucker, A. V. Volotka, S. Fritzsche. 2018-08-06. Maximum Elliptical Dichroism in Atomic Two-Photon Ionization. https://doi.org/10.1103/physrevlett.121.053401

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