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 N\'eel 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.
@article{arxiv.1708.07924,
title = {Quadrupolar quantum criticality on a fractal},
author = {Jonathan D'Emidio and Simon Lovell and Ribhu K. Kaul},
journal= {arXiv preprint arXiv:1708.07924},
year = {2018}
}