graph-states-coherent-info

This MATLAB code computes the coherent information of a graph state under arbitrary i.i.d. Pauli noise, implementing Algorithm 1 in the paper

"Error Tresholds for Arbitrary Pauli Noise", Johannes Bausch and Felix Leditzky, arXiv:1910.00471

Files

• pauli_action.m: Main function that computes the coherent information of a graph state given by the adjacency matrix of the graph.
• get_U_subsets.m: Auxiliary function that is either automatically invoked by pauli_action.m or precomputed by the user.
• examples.m: Contains some examples that illustrate how to best use the code.

Usage

The code works with a standard MATLAB installation and does not require any special packages or add-ons.

For a C++ implementation of Algorithm of our paper that exploits the graph state's symmetries, see https://github.com/rumschuettel/CoffeeCode.