Quantum Lego Expansion Pack: Enumerators from Tensor Networks

Understand

We provide the first tensor network method for computing quantum weight enumerator polynomials in the most general form.

• If a quantum code has a known tensor network construction of its encoding map, our method is far more efficient, and in some cases exponentially faster than the existing approach.
• As a corollary, it produces decoders and an algorithm that computes the code distance.
• For non-(Pauli)-stabilizer codes, this constitutes the current best algorithm for computing the code distance.