2020/06/30 by Darshan G. Joshi, Subir Sachdev
Physics and Astronomy · #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.102.165146
published as Phys. Rev. B 102, 165146 (2020) · 11+11 pages, 6 figures; (v2) Added clarifications and references
arxiv created 2020/09/09 · arxiv updated 2020/10/28
A previous work (Joshi et al., arXiv:1912.08822) found a deconfined critical point at non-zero doping in a t-J model with all-to-all and random hopping and spin exchange, and argued for its relevance to the phenomenology of the cuprates. We extend this model to include all-to-all and random density-density interactions of mean-square strength K. In a fixed realization of the disorder, and for specific values of the hopping, exchange, and density interactions, the model is supersymmetric; but, we find no supersymmetry after independent averages over the interactions. Using the previously developed renormalization group analysis, we find a new fixed point at non-zero K. However, this fixed point is unstable towards the previously found fixed point at K=0 in our perturbative analysis. We compute the exponent characterizing density fluctuations at both fixed points: this exponent determines the spectrum of electron energy-loss spectroscopy.