Duality of the random model and the quantum toric code

Abstract

We study the phase diagrams of random models with bimodal randomness, especially the random bond Ising model and the random plaquette gauge model from the viewpoint of quantum information theory. Using Fourier transformation in conjunction with the replica trick, we show that these models have a common structure under duality transformation. This observation enables us to derive a conjecture on the exact location of the multicritical point and lead the accuracy threshold of the toric code, which is one of the topological quantum memories. © 2005 The Physical Society of Japan.