(GQR43/AFC1) Regime-resolved bandwidth robustness in cavity-enhanced atomic frequency comb quantum memories

Abstract: We present a regime-resolved modelling study of cavity-enhanced Eu3+:Y2SiO5atomic frequency comb (AFC) quantum memories that quantifies bandwidth robustness acrosscontrast and comb-bandwidth parameter space. Using Kramers–Kronig–consistent susceptibilityreconstruction and frequency-domain cavity transfer modelling with representative integrated-device parameters, we construct contrast–bandwidth response atlases for wide- and narrow-cavityregimes. While first-order dispersion cancellation between spectral pit and AFC structures canbe achieved, robustness is shown to be governed by higher-order susceptibility curvature undercavity phase feedback. For representative configurations, cavity narrowing reduces admissibleoperating volume by approximately 35–40%, despite comparable peak echo amplitude. Theatlas methodology provides a quantitative tolerance-analysis framework for integrated rare-earthphotonic memories. Full 70 article programme https://github.com/jamessutton600613-png/GQR/blob/main/Programme_Index.md The programme contains both standalone and self referencing articles. These can all be read as notes in proof of GQR1.