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arXiv · 1303.1649

Giant phase modulation in a Mach-Zehnder exciton-polariton interferometer

C. Sturm·D. Tanese·H. S. Nguyen·H. Flayac·E. Gallopin·A. Lemaître·I. Sagnes·D. Solnyshkov·A. Amo·G. Malpuech·J. Bloch
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Abstract

We report on a new mechanism of giant phase modulation. The phenomenon arises when a dispersed photonic mode (slow light) strongly couples to an excitonic resonance. In such a case, even a small amount of optically injected carriers creates a potential barrier for the propagating exciton-polariton which provokes a considerable phase shift. We evidence this effect by fabricating an exciton-polariton Mach-Zehnder interferometer, modulating the output intensity by constructive or destructive interferences controlled by optical pumping of a micrometric size area. The figure of merit for a {\pi} phase shift, defined by the control power times length of the modulated region, is found at least one order of magnitude smaller than slow light photonic crystal waveguides.

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C. Sturm, D. Tanese, H. S. Nguyen, H. Flayac, E. Gallopin, A. Lemaître, I. Sagnes, D. Solnyshkov, A. Amo, G. Malpuech, J. Bloch. 2013-03-07. Giant phase modulation in a Mach-Zehnder exciton-polariton interferometer. https://doi.org/10.1038/ncomms4278

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