Revealing laser-coherent electron features using phase-of-the-phase spectroscopy

V. A. Tulsky; B. Krebs; J. Tiggesbäumker; D. Bauer

doi:10.1088/1361-6455/ab69ab

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arXiv · 1911.00477

Revealing laser-coherent electron features using phase-of-the-phase spectroscopy

V. A. Tulsky·B. Krebs·J. Tiggesbäumker·D. Bauer

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Abstract

Phase-of-the-phase (PoP) spectroscopy is extended to two-color laser fields having a circularly counter-rotating polarization. In particular, the higher harmonics of the (two-color) phase information are analyzed in order to extract the laser-coherent part of the photoelectron spectra taken under complex target conditions. We illustrate this with a proof-of-principle simulation by considering strong-field electron emission from argon atoms within helium nanodroplets under realistic experimental conditions, i.e., a limited number of photoemission events. Multiple elastic scattering on neutral helium atoms creates a laser-incoherent background, but the higher harmonics of the PoP-signal allow to resolve the coherent contribution to the photoemission.

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V. A. Tulsky, B. Krebs, J. Tiggesbäumker, D. Bauer. 2019-11-01. Revealing laser-coherent electron features using phase-of-the-phase spectroscopy. https://doi.org/10.1088/1361-6455/ab69ab

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