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arXiv · 2101.06642

Nonlinearity-induced reciprocity breaking in a single non-magnetic Taiji resonator

A. Muñoz de las Heras·R. Franchi·S. Biasi·M. Ghulinyan·L. Pavesi·I. Carusotto
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Abstract

We report on the demonstration of an effective, nonlinearity-induced non-reciprocal behavior in a single non-magnetic multi-mode Taiji resonator. Non-reciprocity is achieved by a combination of an intensity-dependent refractive index and of a broken spatial reflection symmetry. Continuous wave power dependent transmission experiments show non-reciprocity and a direction-dependent optical bistability loop. These can be explained in terms of the unidirectional mode coupling that causes an asymmetric power enhancement in the resonator. The observations are quantitatively reproduced by a numerical finite-element theory and physically explained by an analytical coupled-mode theory. This nonlinear Taiji resonator has the potential of being the building block of large arrays where to study topological and/or non-Hermitian physics. This represents an important step towards the miniaturization of nonreciprocal elements for photonic integrated networks.

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A. Muñoz de las Heras, R. Franchi, S. Biasi, M. Ghulinyan, L. Pavesi, I. Carusotto. 2021-01-17. Nonlinearity-induced reciprocity breaking in a single non-magnetic Taiji resonator. https://doi.org/10.1103/physrevapplied.15.054044

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