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arXiv · 1907.11677

Doublon bottleneck in the ultrafast relaxation dynamics of hot electrons in 1T-TaS_2

Isabella Avigo·Friedemann Queisser·Ping Zhou·Manuel Ligges·Kai Rossnagel·Ralf Schützhold·Uwe Bovensiepen
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Abstract

Employing time-resolved photoelectron spectroscopy we analyze the relaxation dynamics of hot electrons in the charge density wave / Mott material 1T-TaS_2. At 1.2 eV above the Fermi level we observe a hot electron lifetime of 12 +- 5 fs in the metallic state and of 60 +- 10 fs in the broken symmetry ground state - a direct consequence of the reduced phase space for electron-electron scattering determined by the Mott gap. Boltzmann equation calculations which account for the interaction of hot electrons in a Bloch band with a doublon-holon excitation in the Mott state provide insight into the unoccupied electronic structure in the correlated state.

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Isabella Avigo, Friedemann Queisser, Ping Zhou, Manuel Ligges, Kai Rossnagel, Ralf Schützhold, Uwe Bovensiepen. 2019-07-26. Doublon bottleneck in the ultrafast relaxation dynamics of hot electrons in 1T-TaS_2. https://doi.org/10.1103/physrevresearch.2.022046

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