Calculating state-to-state transition probabilities within TDDFT

Nina Rohringer; Simone Peter; Joachim Burgdörfer

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Calculating state-to-state transition probabilities within TDDFT

Nina Rohringer·Simone Peter·Joachim Burgdörfer

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Abstract

The determination of the elements of the S-matrix within the framework of time-dependent density-functional theory (TDDFT) has remained a widely open question. We explore two different methods to calculate state-to-state transition probabilities. The first method closely follows the extraction of the S-matrix from the time-dependent Hartree-Fock approximation. This method suffers from cross-channel correlations resulting in oscillating transition probabilities in the asymptotic channels. An alternative method is proposed which corresponds to an implicit functional in the time-dependent density. It gives rise to stable and accurate transition probabilities. An exactly solvable two-electron system serves as benchmark for a quantitative test.

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Nina Rohringer, Simone Peter, Joachim Burgdörfer. 2005-11-16. Calculating state-to-state transition probabilities within TDDFT. https://arxiv.org/abs/quant-ph/0511167

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