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arXiv · 1004.4790

Ultrafast melting of a charge-density wave in the Mott insulator 1T-TaS2

S. Hellmann·M. Beye·C. Sohrt·T. Rohwer·F. Sorgenfrei·H. Redlin·M. Kalläne·M. Marczynski-Bühlow·F. Hennies·M. Bauer·A. Föhlisch·L. Kipp·W. Wurth·K. Rossnagel
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Abstract

Femtosecond time-resolved core-level photoemission spectroscopy with a free-electron laser is used to measure the atomic-site specific charge-order dynamics in the charge-density-wave/Mott insulator 1T-TaS2. After strong photoexcitation, a prompt loss of charge order and subsequent fast equilibration dynamics of the electron-lattice system are observed. On the time scale of electron-phonon thermalization, about 1 ps, the system is driven across a phase transition from a long-range charge ordered state to a quasi-equilibrium state with domain-like short-range charge and lattice order. The experiment opens the way to study the nonequilibrium dynamics of condensed matter systems with full elemental, chemical, and atomic site selectivity.

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S. Hellmann, M. Beye, C. Sohrt, T. Rohwer, F. Sorgenfrei, H. Redlin, M. Kalläne, M. Marczynski-Bühlow, F. Hennies, M. Bauer, A. Föhlisch, L. Kipp, W. Wurth, K. Rossnagel. 2010-04-27. Ultrafast melting of a charge-density wave in the Mott insulator 1T-TaS2. https://doi.org/10.1103/physrevlett.105.187401

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