(GQR59) Zen and the Art of Music: What Quantum Memory Combs Reveal About High Fidelity

JAMES SUTTON

Published Apr 4, 2025• 0 citations

Abstract

High signal integrity in quantum memory systems is often assumed to be recoverable throughdownstream optimisation. Here, using a model of atomic frequency comb (AFC) dynamics, weshow that signal integrity is instead determined at formation. Across a broad parameter space,the system exhibits a transient regime in which signal amplitude remains close to a clean referencewhile directional asymmetry emerges between forward and backward evolution (AB̸ = BA). Thisdefines an echological regime, characterised by low signal disturbance and loss of path equivalence.Time-resolved analysis reveals a universal transition from an early structured regime to a noise-dominated state, with the transition time largely independent of comb parameters. Apparent late-time stability is shown to arise from loss of accessible structure rather than recovery of the originalsignal. Comparison of observables further demonstrates that convergence in raw intensity canmask divergence in more sensitive representations, indicating that stability is strongly observable-dependent.These results imply that AFC systems, in their symmetric form, act as recurrence substratesrather than complete memory devices. Reliable memory requires an additional selection or filter-ing layer capable of suppressing ambiguous components and restoring directional asymmetry in acontrolled manner. More generally, the findings establish that signal integrity is not produced bycorrection, but emerges when system parameters are aligned with a constrained operating regimeat formation. 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.19370496

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