2026-02-26 理化学研究所,東京大学,科学技術振興機構
光振幅に生じたノイズを量子的な情報を壊さないよう検知し、元に戻す仕組み（誤り訂正）
＜関連情報＞
- https://www.riken.jp/press/2026/20260226_1/index.html
- https://www.nature.com/articles/s41467-026-69036-5
一般ノイズ下における連続変数フォールトトレラント量子計算 Continuous-variable fault-tolerant quantum computation under general noise
Takaya Matsuura,Nicolas C. Menicucci & Hayata Yamasaki
Nature Communications Published:26 February 2026
DOI:https://doi.org/10.1038/s41467-026-69036-5
Abstract
Quantum error-correcting code in continuous-variable (CV) systems attracts much attention due to its flexibility and high resistance against specific noise. However, the theory of fault tolerance in CV systems is premature and lacks a general strategy to translate noise in CV systems into noise in logical qubits, leading to severe restrictions on correctable noise models. In this paper, we show that Markovian-type noise in CV systems is translated into Markovian-type noise in the logical qubits through the Gottesman-Kitaev-Preskill code. We analyze an upper bound on the resulting noise strength in terms of our newly introduced noise parameterization. Combined with the established threshold theorem of concatenated codes against Markovian-type noise, we show that CV quantum computation has a fault-tolerant threshold against general Markovian-type noise, closing the existing crucial gap in CV quantum computation. We also give a new insight into the fact that careful management of the energy of a state is required to achieve fault tolerance in CV systems.
