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arXiv:2606.30315

All-optical switching of continuous-variable entanglement in an absorption-suppressed plasmonic nanodimer

Elif Ozturk, Mehmet Gunay, Ramazan Sahin, Mehmet Emre Tasgin

quant-phcond-mat.mes-hallphysics.opticsSubmitted Jun 29, 2026• Announced Jun 30, 2026• 0 citations
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Abstract

A subwavelength quantum-photonic circuit element should simultaneously generate nonclassical light, suppress plasmonic loss, and remain dynamically tunable. We show that an orthogonal plasmonic nanorod dimer can satisfy all three requirements. A phase-locked control polarization induces plasmonic refractive-index enhancement, driving the probe response toward a near-zero-extinction regime while simultaneously tuning the local second-harmonic parametric interaction. The resulting nonlinear plasmonic source operates in an absorption-suppressed regime and enables all-optical control of quantum correlations. We demonstrate switchable logarithmic negativity and single-mode nonclassicality, establishing a route toward actively tunable quantum-plasmonic circuit elements operating well below the diffraction limit.

Comments
5 pages, 3 figures

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