2026/04/09 by Xiang-Jiang Chen, Hao-Miao Jiang, Liu-Jun Wang +1 · 1 voice
Physics and Astronomy · #quant-ph
The Gottesman-Kitaev-Preskill (GKP) code is a promising bosonic candidate for realizing fault-tolerant quantum computation. Among existing error-correction protocols for GKP code, the Steane-type scheme is a canonical and widely adopted paradigm, yet its intrinsic noise propagation pattern limits further performance improvement. In this work, we propose a preprocessing-based Steane-type (P-Steane) scheme, which introduces a tunable preprocessing stage with squeezing parameters a and b to actively reshape noise propagation, thereby constituting a parameter framework. This framework spans a spectrum of protocols beyond existing methods, reproducing the performance of both the ME-Steane scheme (a=1, b=1) and the teleportation-based scheme (a=1/√(2), b=√(2)) as special cases. Crucially, in the small-noise regime and when the data qubit is noisier than the ancilla qubits, P-Steane scheme achieves the minimum product of position- and momentum-quadrature output noise variances when 2a = b, and consistently outperforms the ME-Steane scheme within a specific squeezing-parameter range under this condition.