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arXiv · 2403.04209

Phonon state tomography of electron correlation dynamics in optically excited solids

Mattia Moroder·Matteo Mitrano·Ulrich Schollwöck·Sebastian Paeckel·John Sous
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Abstract

We introduce phonon state tomography (PST) as a diagnostic probe of electron dynamics in solids whose phonons are optically excited by a laser pulse at initial time. Using a projected-purified matrix-product states algorithm, PST decomposes the exact correlated electron-phonon wavefunction into contributions from purely electronic states corresponding to statistically typical configurations of the optically accessible phononic response, enabling a 'tomographic' reconstruction of the electronic dynamics generated by the phonons. Thus, PST may be used to diagnose electronic behavior in experiments that access only the phonon response, such as thermal diffuse x-ray and electron scattering. We study the dynamics of a metal whose infrared phonons are excited by an optical pulse at initial time and use it to simulate the sample-averaged momentum-resolved phonon occupancy and accurately reconstruct the electronic correlations. We also use PST to analyze the influence of different pulse shapes on the light-induced enhancement and suppression of electronic correlations.

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Mattia Moroder, Matteo Mitrano, Ulrich Schollwöck, Sebastian Paeckel, John Sous. 2024-03-07. Phonon state tomography of electron correlation dynamics in optically excited solids. https://doi.org/10.1021/acs.nanolett.4c04314

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