Quantum computation from dynamic automorphism codes

TL;DR

This paper introduces dynamic automorphism (DA) codes, a new class of quantum error-correcting codes that enable logical operations through low-weight measurement sequences, advancing towards universal quantum computation.

Contribution

The paper presents DA codes, including the DA color code, which generalize Floquet codes and demonstrate how to implement a universal set of logical gates using measurement sequences.

Findings

DA color code encodes N logical qubits on N triangular patches.

All 72 automorphisms of the 2D color code can be realized.

A non-Clifford logical gate is achievable with a 3D DA color code.

Abstract

We propose a new model of quantum computation comprised of low-weight measurement sequences that simultaneously encode logical information, enable error correction, and apply logical gates. These measurement sequences constitute a new class of quantum error-correcting codes generalizing Floquet codes, which we call dynamic automorphism (DA) codes. We construct an explicit example, the DA color code, which is assembled from short measurement sequences that can realize all 72 automorphisms of the 2D color code. On a stack of $N$ triangular patches, the DA color code encodes $N$ logical qubits and can implement the full logical Clifford group by a sequence of two- and, more rarely, three-qubit Pauli measurements. We also make the first step towards universal quantum computation with DA codes by introducing a 3D DA color code and showing that a non-Clifford logical gate can be realized by adaptive two-qubit measurements.