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arXiv · 1012.3691

Impurity spin texture at a Néel-Valence Bond Solid critical point in $d=2$ SU(3) quantum antiferromagnets

Argha Banerjee·Kedar Damle·Fabien Alet
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Abstract

We study the impurity physics at a continuous quantum phase transition from an SU(3) symmetric Néel ordered state to a valence bond solid state that breaks lattice symmetries, using quantum Monte Carlo techniques. This continuous transition is expected to be an example of `deconfined criticality' in an SU(3) symmetric system. We find that the spin-texture induced by a missing-spin defect at the transition takes on a finite-size scaling form consistent with expectations from standard scaling arguments at a scale-invariant quantum critical point, albeit with significant subleading power-law finite size corrections that we analyze in detail. Together with recently-found logarithmic violations of scaling at similar continuous transitions in the SU(2) case, our results provide indirect evidence for the existence of operators that become marginal as $N$ is reduced to 2 in the field theoretical description of these deconfined critical points.

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Argha Banerjee, Kedar Damle, Fabien Alet. 2010-12-16. Impurity spin texture at a Néel-Valence Bond Solid critical point in $d=2$ SU(3) quantum antiferromagnets. https://doi.org/10.1103/physrevb.83.235111

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