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Quasiparticle excitations in frustrated antiferromagnets

A. E. Trumper·C. J. Gazza·L. O. Manuel
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Abstract

We have computed the quasiparticle wave function corresponding to a hole injected in a triangular antiferromagnet. We have taken into account multi-magnon contributions within the self consistent Born approximation. We have found qualitative differences, under sign reversal of the integral transfer t, regarding the multi-magnon components and the own existence of the quasiparticle excitations. Such differences are due to the subtle interplay between magnon-assisted and free hopping mechanisms. We conclude that the conventional quasiparticle picture can be broken by geometrical frustration without invoking spin liquid phases.

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A. E. Trumper, C. J. Gazza, L. O. Manuel. 2004-10-08. Quasiparticle excitations in frustrated antiferromagnets. https://doi.org/10.1016/j.physb.2004.09.058

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