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arXiv · 2409.18175

Fault-Tolerant Logical Clifford Gates from Code Automorphisms

Hasan Sayginel·Stergios Koutsioumpas·Mark Webster·Abhishek Rajput·Dan E Browne
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Abstract

We study the implementation of fault-tolerant logical Clifford gates on stabilizer quantum error correcting codes based on their symmetries. Our approach is to map the stabilizer code to a binary linear code, compute its automorphism group, and impose constraints based on the Clifford operators permitted. We provide a rigorous formulation of the method for finding automorphisms of stabilizer codes and generalize ZX-dualities to non-CSS codes. We provide a Python package implementing our algorithms which uses the computational algebra system MAGMA. Our algorithms map automorphism group generators to physical circuits, calculate Pauli corrections based on the destabilizers of the code, and determine their logical action. We discuss the fault tolerance of the circuits and include examples of gates through automorphisms for the [[4,2,2]] and perfect [[5,1,3]] codes, bivariate bicycle codes, and the best known distance codes.

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Hasan Sayginel, Stergios Koutsioumpas, Mark Webster, Abhishek Rajput, Dan E Browne. 2025-05-09. Fault-Tolerant Logical Clifford Gates from Code Automorphisms. https://arxiv.org/abs/2409.18175

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