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arXiv · 1309.5119

Wave packet dynamics in the one-dimensional extended Hubbard model

K. A. Al-Hassanieh·Julian Rincon·E. Dagotto·G. Alvarez
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Abstract

Using time-dependent density-matrix renormalization group, we study the time evolution of electronic wave packets in the one-dimensional extended Hubbard model with on-site and nearest neighbor repulsion, U and V, respectively. As expected, the wave packets separate into spin-only and charge-only excitations (spin-charge separation). Charge and spin velocities exhibit non-monotonic dependence on V. For small and intermediate values of V, both velocities increase with V. However, the charge velocity exhibits a stronger dependence than that of the spin, leading to a more pronounced spin-charge separation. Charge fractionalization, on the other hand, is weakly affected by V. The results are explained in terms of Luttinger liquid theory in the weak-coupling limit, and an effective model in the strong-coupling regime.

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K. A. Al-Hassanieh, Julian Rincon, E. Dagotto, G. Alvarez. 2013-09-19. Wave packet dynamics in the one-dimensional extended Hubbard model. https://doi.org/10.1103/physrevb.88.045107

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