Ultrafast X-ray Diffraction Probe of Coherent Spin-state Dynamics in Molecules

Xiaoyu Mi; Ming Zhang; Zheng Li

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arXiv · 2401.00259

Ultrafast X-ray Diffraction Probe of Coherent Spin-state Dynamics in Molecules

Xiaoyu Mi·Ming Zhang·Zheng Li

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Abstract

We propose an approach to probe coherent spin-state dynamics of molecules using circularly polarized hard x-ray pulses. For the dynamically aligned nitric oxide molecules in a coherent superposition spin-orbit coupled electronic state that can be prepared through stimulated Raman scattering, we demonstrate the capability of ultrafast x-ray diffraction to not only reveal the quantum beating of the coherent spin-state wave packet, but also image the spatial spin density of the molecule. With circularly polarized ultrafast x-ray diffraction signal, we show that the electronic density matrix can be retrieved. The spatio-temporal resolving power of ultrafast x-ray diffraction paves the way for tracking transient spatial wave function in molecular dynamics involving spin degree of freedom.

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Xiaoyu Mi, Ming Zhang, Zheng Li. 2023-12-30. Ultrafast X-ray Diffraction Probe of Coherent Spin-state Dynamics in Molecules. https://arxiv.org/abs/2401.00259

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