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This content will become publicly available on August 1, 2025

Title: Quantum spherical codes
As with classical computers, quantum computers require error-correction schemes to reliably perform useful large-scale calculations. The nature and frequency of errors depends on the quantum computing platform, and although there is a large literature on qubit-based coding, these are often not directly applicable to devices that store information in bosonic systems such as photonic resonators. Here, we introduce a framework for constructing quantum codes defined on spheres by recasting such codes as quantum analogues of the classical spherical codes. We apply this framework to bosonic coding, and we obtain multimode extensions of the cat codes that can outperform previous constructions but require a similar type of overhead. Our polytope-based cat codes consist of sets of points with large separation that, at the same time, form averaging sets known as spherical designs. We also recast concatenations of Calderbank–Shor–Steane codes with cat codes as quantum spherical codes, which establishes a method to autonomously protect against dephasing noise.  more » « less
Award ID(s):
2104489 2110113 2330909
NSF-PAR ID:
10538113
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Springer Nature
Date Published:
Journal Name:
Nature Physics
Volume:
20
Issue:
8
ISSN:
1745-2473
Page Range / eLocation ID:
1300 to 1305
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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