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Spinon deconfinement in doped frustrated quantum antiferromagnets

Didier Poilblanc·Andreas Laeuchli·Matthieu Mambrini·Frederic Mila
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Abstract

The confinement of a spinon liberated by doping two-dimensional frustrated quantum antiferromagnets with a non-magnetic impurity or a mobile hole is investigated. For a static vacancy, an intermediate behavior between complete deconfinement (kagome) and strong confinement (checkerboard) is identified in the J_1{-}J_2{-}J_3 model on the square lattice, with the emergence of two length scales, a spinon confinement length larger than the magnetic correlation length. For mobile holes, this translates into an extended spinon-holon boundstate allowing one to bridge momentum (ARPES spectral function) and real space (STM) experimental observations. These features provide clear evidence for a nearby "deconfined critical point" in a doped microscopic model.

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Didier Poilblanc, Andreas Laeuchli, Matthieu Mambrini, Frederic Mila. 2005-12-21. Spinon deconfinement in doped frustrated quantum antiferromagnets. https://doi.org/10.1103/physrevb.73.100403

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