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arXiv · 1808.05512

Density-matrix description of partially coherent spin-orbit wave packets produced in short-laser-pulse photodetachment

S. M. K. Law·G. F. Gribakin
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Abstract

We investigate orbital alignment dynamics within the valence shell of atoms in coherently excited $j=3/2,1/2$ fine-structure manifolds generated by short-pulse photodetachment of F$^-$, Cl$^-$ and Br$^-$ anions. Using Keldysh-type theory, we calculate the density matrix of the residual atoms generated by few-cycle pulses, whose elements determine the populations and coherence among the electronic states. Our calculations demonstrate that the degree of atomic coherence can be represented by a near universal function of the ratio between the pulse duration $\tilde{\tau}_p$ and the beat period $\tau_{j'j}$ of the atomic system, which allows one to characterize the coherence generated in atomic states.

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S. M. K. Law, G. F. Gribakin. 2018-08-16. Density-matrix description of partially coherent spin-orbit wave packets produced in short-laser-pulse photodetachment. https://arxiv.org/abs/1808.05512

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