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arXiv · 1708.07924

Quadrupolar quantum criticality on a fractal

Jonathan D'Emidio·Simon Lovell·Ribhu K. Kaul
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Abstract

We study the ground state ordering of quadrupolar ordered $S=1$ magnets as a function of spin dilution probability $p$ on the triangular lattice. In sharp contrast to the ordering of $S=1/2$ dipolar Néel magnets on percolating clusters, we find that the quadrupolar magnets are quantum disordered at the percolation threshold, $p=p^*$. Further we find that long-range quadrupolar order is present for all $p<p^*$ and vanishes first exactly at $p^*$. Strong evidence for scaling behavior close to $p^*$ points to an unusual quantum criticality without fine tuning that arises from an interplay of quantum fluctuations and randomness.

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Jonathan D'Emidio, Simon Lovell, Ribhu K. Kaul. 2017-08-26. Quadrupolar quantum criticality on a fractal. https://doi.org/10.1103/physrevb.97.184430

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