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arXiv · 2607.26898

Revival of transport reciprocity via quantum interference in asymmetric nonlinear devices

Rupak Bag·Dibyendu Roy
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Abstract

Structural asymmetry combined with optical nonlinearity often leads to nonreciprocal light transport. We explore the mechanism by which 1-photon interference effects can revive reciprocity in such nonlinear models. To this end, we study correlated 2-photon scattering where an artificial atom is asymmetrically (a) side-coupled to an infinite waveguide at two spatially separated points, and (b) direct-coupled to two semi-infinite waveguides. The setup (a) gives robust reciprocal transport for the two photons. However, the setup (b) shows a transition from a nonreciprocal to a reciprocal regime by tuning the interference effect via an additional tunneling path for photons between the two waveguides.

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Rupak Bag, Dibyendu Roy. 2026-07-29. Revival of transport reciprocity via quantum interference in asymmetric nonlinear devices. https://arxiv.org/abs/2607.26898

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