Random encoders and expurgation improve 1,873 entries of the Grassl qubit code tables

arXiv:2611.08744v1 Announce Type: new Abstract: I report 192 explicit binary stabilizer codes $[[n,k,d]]$ with $53\le n\le 254$ and $5\le d\le 13$ whose minimum distance exceeds the lower bound listed in Grassl's code tables at the same $(n,k)$: 161 codes by one and 31 by two. Through the standard propagation rules they raise 1,873 entries of the table. For 190 of the codes, a random Clifford encoder is followed by expurgation: every logical operator of weight below the target distance is enumerated, and a few logical operators are promoted to stabilizers so that each low-weight one anticommutes with at least one of them. The other two are obtained by puncturing a code from the table and repairing it in the same way.