(GQR45/AFC3) Geometry–Coherence Coupling and Quantum Admissibility in Cavity-Enhanced Rare-Earth AFC Memories.

JAMES SUTTON

Published Feb 18, 2026• 0 citations

Abstract

Cavity-enhanced atomic frequency comb (AFC) quantum memories are typicallyanalyzed in terms of spectral preparation and cavity efficiency. However, geometric toleranceand optical coherence jointly determine quantum admissibility. We introduce a coupledgeometry–coherence admissibility framework in which strain-induced inhomogeneity reduceseffective coherence time 𝑇2,eff , while cavity-induced ridge drift defines a geometric toleranceratio 𝜌. We show that quantum operation requires simultaneous satisfaction of geometric andcoherence constraints, yielding a dominance decomposition and collapse boundary in strainspace. The framework clarifies how cavity design and material coherence budgets jointly boundachievable storage times. 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.

DOI: 10.5281/zenodo.18676143

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