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arXiv · 1803.02020

Light-Matter Interactions via the Exact Factorization Approach

Norah M. Hoffmann·Heiko Appel·Angel Rubio·Neepa T. Maitra
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Abstract

The exact factorization approach, originally developed for electron-nuclear dynamics, is extended to light-matter interactions within the dipole approximation. This allows for a Schrodinger equation for the photonic wavefunction, in which the potential contains exactly the effects on the photon field of its coupling to matter. We illustrate the formalism and potential for a two-level system representing the matter, coupled to an infinite number of photon modes in the Wigner-Weisskopf approximation, as well as a single mode with various coupling strengths. Significant differences are found with the potential used in conventional approaches, especially for strong-couplings. We discuss how our exact factorization approach for light-matter interactions can be used as a guideline to develop semiclassical trajectory methods for efficient simulations of light-matter dynamics.

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Norah M. Hoffmann, Heiko Appel, Angel Rubio, Neepa T. Maitra. 2018-05-03. Light-Matter Interactions via the Exact Factorization Approach. https://doi.org/10.1140/epjb%2Fe2018-90177-6

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