Entanglement Entropy Scaling in the Disordered Golden Chain

ORAL

Abstract

For pure critical spin chains, the scaling of the entanglement entropy of a region of size $L$ with its complement is proportional to $\log L$ with the constant of proportionality being the central charge of the associated conformal field theory. Certain strongly disordered spin chains exhibit critical points with similar $\log L$ scaling. Here we study the disordered golden chain (modeled by fibonacci anyons), and show that the usual random singlet critical point achieved with random antiferromagnetic (AFM) couplings is unstable to ferromagnetic (FM) perturbations. We identify the new mixed FM-AFM fixed point and compute its entanglement entropy scaling.

–

Authors

  • Lukasz Fidkowski

    Caltech

  • Gil Refael

    Physics Department, California Institute of Technology, Caltech

  • Nick Bonesteel

    FSU, FSU \& NHMFL, Department of Physics and NHMFL, Florida State University

  • Kun Yang

    FSU, FSU \& NHMFL, National High Magnetic Field Lab and Florida State University, National High Magnetic Field Laboratory, Florida State University

  • Joel Moore

    Berkeley, Department of Physics, University of California, and Material Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA, Department of Physics, UC Berkeley, and Materials Sciences Division, Lawrence Berkeley National Laboratory, UC Berkeley