Semi-Dirac Transport and Anisotropic Localization in Polariton Honeycomb Lattices
B. Real, O. Jamadi, M. Milićević, N. Pernet, P. St-Jean, T. Ozawa, G. Montambaux, I. Sagnes, A. Lemaître, L. Le Gratiet, A. Harouri, S. Ravets, J. Bloch, A. Amo
Compression dramatically changes the transport and localization properties of graphene. This is intimately related to the change of symmetry of the Dirac cone when the particle hopping is different along different directions of the lattice. In particular, for a critical compression, a semi-Dirac cone is formed with massless and massive dispersions along perpendicular directions. Here we show direct evidence of the highly anisotropic transport of polaritons in a honeycomb lattice of coupled micropillars implementing a semi-Dirac cone. If we optically induce a vacancy-like defect in the lattice, we observe an anisotropically localized polariton distribution in a single sublattice, a consequence of the semi-Dirac dispersion. Our work opens up new horizons for the study of transport and localization in lattices with chiral symmetry and exotic Dirac dispersions.
Spin-momentum locking of polariton edge states in honeycomb lattices
Universidad Autónoma de Madrid（马德里自治大学）；Università di Padova（帕多瓦大学）；Indian Institute of Technology Bombay（孟买印度理工学院）；Indian Institute of Technology Dharwad（达尔瓦德印度理工学院）；Julius-Maximilians-Universität Würzburg（维尔茨堡朱利叶斯-马克西米利安大学）
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