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arXiv · 1710.03584

Magnetic spin-orbit interaction directs Bloch surface waves

Mengjia Wang·Hongyi Zhang·Tatiana Kovalevitch·Roland Salut·Myun-Sik Kim·Miguel Angel Suarez·Maria-Pilar Bernal·Hans-Peter Herzig·Huihui Lu·Thierry Grosjean
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Abstract

We study the directional excitation of optical surface waves controlled by the magnetic field of light. We theoretically predict that a spinning magnetic dipole develops a tunable unidirectional coupling of light to TE-polarized Bloch surface waves (BSWs). Experimentally, we show that the helicity of light projected onto a subwavelength groove milled in the top layer of a 1D photonic crystal (PC) controls the power distribution between two TE-polarized BSWs excited on both sides of the groove. Such a phenomenon is shown to be mediated solely by the helicity of the magnetic field of light, thus revealing a magnetic spin-orbit interaction. Remarkably, this magnetic optical effect is clearly observed with a near-field coupler governed by an electric dipole moment: it is of the same order of magnitude as the electric optical effects involved in the coupling. The magnetic spin-orbit interaction opens new degrees of freedom in the manipulation of light and offers appealing novel opportunities in the development of integrated optical functionalities.

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Mengjia Wang, Hongyi Zhang, Tatiana Kovalevitch, Roland Salut, Myun-Sik Kim, Miguel Angel Suarez, Maria-Pilar Bernal, Hans-Peter Herzig, Huihui Lu, Thierry Grosjean. 2017-10-11. Magnetic spin-orbit interaction directs Bloch surface waves. https://arxiv.org/abs/1710.03584

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