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Updated: May 29, 2026

A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Quantum entanglement, stratified spaces, and topological matter: towards entanglement-sensitive Langlands data
Kazuki Ikeda1,2, Steven Rayan3,4
1Department of Physics, University of Massachusetts Boston, Boston, MA 02125, United States of America.
None:
Using the spinless Haldane model, we study the witness-filtered Berry curvature, quantum geometric tensor, and quantum Fisher information on the gapped strata of the parameter space and evaluate them through the Fukui-Hatsugai-Suzuki discretization. The filtered quantities isolate the part of the geometric response carried by sublattice coherence: they suppress contributions from regions where the occupied Bloch state is locally A/B-separable and emphasize regions where curvature and coherence coexist. We derive exact lattice identities, reconstruction formulas for the curvature-weighted coherence, and bounds relating the filtered quantum geometric tensor and quantum Fisher information to single-particle mode entanglement. Across the gap-closing stratum, the quantized response changes admit a natural description in terms of Hecke modifications. We elicit a corresponding Langlands viewpoint-not as a full correspondence, but as an organizational principle and as the mathematical shadow of these physical geometric constructions.
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