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DOE OSTI · 1975847

Strong-field nonsequential double photoionization using virtual-detector theory with path summation

Younis, Daniel·Eberly, Joseph H.
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Abstract

We present an ab initio study of the nonsequential strong-field ionization dynamics of a model two-electron atom with helium character. Single- and double-ionization events are characterized and displayed using detector signals extracted at different points in the two-electron two-dimensional space. The double photoelectron momentum distribution is calculated via coherent path-summation over virtual-particle trajectories. A comparison is made between the momentum distributions obtained with the virtual-detector method, the Schrödinger wave function, and the time-dependent surface flux method developed by Tao and Scrinzi [New J. Phys. 14, 013021 (2012)]. Insights into different ionization and electron recollision pathways are gained from detailed virtual-particle tracking and energy-time readouts. Furthermore, this study demonstrates the extension of virtual-detector theory to strong-field multielectron quantum dynamics and highlights the importance of the evolving quantum phase in quasiclassical electron propagation.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS74 ATOMIC AND MOLECULAR PHYSICS97 MATHEMATICS AND COMPUTINGAtomic & molecular processes in external fieldsAtomsComputational strong-field quantum dynamicsDipole approximationElectron-correlation calculationsElectronic excitation & ionizationFirst-principles calculationsHigh-intensity laser-atom interactionInter-electron correlationMultiphoton or tunneling ionization & excitationNonperturbative methodsNonsequential ionizationSchroedinger equationSemiclassical methodsTime-dependent Schrödinger equationVirtual detector method

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Younis, Daniel, Eberly, Joseph H.. 2023-05-30. Strong-field nonsequential double photoionization using virtual-detector theory with path summation. https://doi.org/10.1103/physreva.107.053117

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