LAUSR

We would like to thank C. Xu for useful discussions. A.W.S. was supported by the NSF under Grant No. DMR-1710170 and by a Simons Investigator Grant. P.P. would like to thank the Institute of Physics, Chinese Academy of Sciences, for visitor support. The computational work was performed using the Shared Computing Cluster administered by Boston University's Research Computing Services. We used QUSPIN to check the quantum Monte Carlo simulation against exact diagonalization calculations [27]. (DMR-1710170 - NSF; Simons Investigator Grant)