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arXiv · 0705.3985

Static Holes in the Geometrically Frustrated Bow Tie Ladder

George B. Martins·Wolfram Brenig
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Abstract

We investigate the doping of a geometrically frustrated spin ladder with static holes by a complementary approach using exact diagonalization and quantum dimers. Results for thermodynamic properties, the singlet density of states, the hole-binding energy and the spin correlations will be presented. For the undoped systems the ground state is non-degenerate, with translationally invariant nearest-neighbor spin correlations. In the doped case, we find that static holes polarize their vicinity by a localization of singlets in order to reduce the frustration. This polarization induces short range repulsive forces between two holes and an oscillatory behavior of the long range two-hole energy. For most quantities investigated, we find very good agreement between the quantum dimer approach and the results from exact diagonalization.

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George B. Martins, Wolfram Brenig. 2007-05-27. Static Holes in the Geometrically Frustrated Bow Tie Ladder. https://doi.org/10.1088/0953-8984%2F20%2F41%2F415204

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