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Title: Toward a 2D Local Implementation of Quantum Low-Density Parity-Check Codes
Geometric locality is an important theoretical and practical factor for quantum low-density parity-check (qLDPC) codes that affects code performance and ease of physical realization. For device architectures restricted to two-dimensional (2D) local gates, naively implementing the high-rate codes suitable for low-overhead fault-tolerant quantum computing incurs prohibitive overhead. In this work, we present an error-correction protocol built on a bilayer architecture that aims to reduce operational overheads when restricted to 2D local gates by measuring some generators less frequently than others. We investigate the family of bivariate-bicycle qLDPC codes and show that they are well suited for a parallel syndrome-measurement scheme using fast routing with local operations and classical communication (LOCC). Through circuit-level simulations, we find that in some parameter regimes, bivariate-bicycle codes implemented with this protocol have logical error rates comparable to the surface code while using fewer physical qubits. Published by the American Physical Society2025  more » « less
Award ID(s):
2120757
PAR ID:
10592885
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
PRX Quantum
Date Published:
Journal Name:
PRX Quantum
Volume:
6
Issue:
1
ISSN:
2691-3399
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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