Checking the error correction strength of arbitrary surface code logical   gates
  Topologically quantum error corrected logical gates are complex. Chains of errors can form in space and time and diagonally in spacetime. It is highly nontrivial to determine whether a given logical gate is free of low weight combinations of errors leading to failure. We report a new tool Nestcheck capable of analyzing an arbitrary topological computation and determining the minimum number of errors required to cause failure. 
Thomas J. Milburn and Austin G. Fowler
quant-ph