Data and code for "Fixed laboratory-axis readout of retained qubit information near a Floquet crossing

his dataset accompanies the manuscript "Fixed laboratory-axis readout of retained qubit information near a Floquet crossing" by Matthias Jakob. It provides the numerical data and analysis code for a driven spin-boson benchmark of delayed readout with one fixed laboratory Pauli axis. The estimated parameter is an initial-state mixture coefficient. Each independently prepared copy is measured once at a uniformly sampled, recorded delay, and Fisher information is evaluated locally at the central mixture. The integrated archive contains the primary HEOM comparison and local variations, a study of known input directions, and a broader drive-amplitude scan. Its inventory comprises 315 antipodal solver records, corresponding to 630 endpoint-state propagations: 51 primary records, 30 input-direction records, and 234 amplitude-scan records. Repeated reference calculations are retained; reused control files are not counted as new propagations. Included materials comprise frozen configurations, endpoint Bloch trajectories, available solver logs, analysis and figure scripts, numerical summaries, provenance records, dependency versions, and reproduction instructions. Initial failed diagnostics and their documented resolutions are preserved. ESM1.pdf supplies the matching methods and numerical checks. ESM2.zip is byte-identical to Online Resource 2 in the manuscript package prepared on 3 November 2026. The results include a favorable 15-degree neighborhood within the reconstructed numerical maps and an explicit known-y-input counterexample. Amplitude maxima are sampled extrema; reported width brackets are finite-resolution diagnostics. The study does not establish universal protection of an arbitrary unknown qubit, a specifically non-Markovian advantage, or a certified continuous global optimum. This repository preparation adds documentation and citation metadata; it performs no new HEOM propagation. Component-specific reuse terms are described in LICENSE.txt.