Triangular color codes on trivalent graphs with flag qubits
Abstract
The color code is a topological quantum error-correcting code supporting a variety of valuable fault-tolerant logical gates. Its two-dimensional version, the triangular color code, may soon be realized with currently available superconducting hardware despite constrained qubit connectivity. To guide this experimental effort, we study the storage threshold of the triangular color code against circuit-level depolarizing noise. First, we adapt the Restriction Decoder to the setting of the triangular color code and to phenomenological noise. Then, we propose a fault-tolerant implementation of the stabilizer measurement circuits, which incorporates flag qubits. We show how information from flag qubits can be used in an efficient and scalable way with the Restriction Decoder to maintain the effective distance of the code. We numerically estimate the threshold of the triangular color code to be 0.2%, which is competitive with the thresholds of other topological quantum codes. We also prove that 1-flag stabilizer measurement circuits are sufficient to preserve the full code distance, which may be used to find simpler syndrome extraction circuits of the color code.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 01, 2020
- Source ID
- 10.1088/1367-2630/ab68fd
Entities
People
- Aleksander Kubica
- Christopher Chamberland
- Guanyu Zhu
- Theodore J. Yoder
Organizations
- Intelligence Advanced Research Projects Activity