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arXiv · 1609.06485

Orbital edge states in a photonic honeycomb lattice

Marijana Milićević·Tomoki Ozawa·Gilles Montambaux·Iacopo Carusotto·Elisabeth Galopin·Aristide Lemaître·Luc Le Gratiet·Isabelle Sagnes·Jacqueline Bloch·Alberto Amo
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Abstract

We experimentally reveal the emergence of edge states in a photonic lattice with orbital bands. We use a two-dimensional honeycomb lattice of coupled micropillars whose bulk spectrum shows four gapless bands arising from the coupling of $p$-like photonic orbitals. We observe zero-energy edge states whose topological origin is similar to that of conventional edge states in graphene. Additionally, we report novel dispersive edge states that emerge not only in zigzag and bearded terminations, but also in armchair edges. The observations are reproduced by tight-binding and analytical calculations. Our work shows the potentiality of coupled micropillars in elucidating some of the electronic properties of emergent 2D materials with orbital bands.

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Marijana Milićević, Tomoki Ozawa, Gilles Montambaux, Iacopo Carusotto, Elisabeth Galopin, Aristide Lemaître, Luc Le Gratiet, Isabelle Sagnes, Jacqueline Bloch, Alberto Amo. 2016-09-21. Orbital edge states in a photonic honeycomb lattice. https://doi.org/10.1103/physrevlett.118.107403

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