Semi-Dirac Transport and Anisotropic Localization in Polariton Honeycomb Lattices

B. Real (1) , O. Jamadi (1) , M. Milićević (2) , N. Pernet (2) , P. St-Jean (2) , T. Ozawa , G. Montambaux (3) , I. Sagnes (2) , A. Lemaître (2) , L. Le Gratiet (2) , A. Harouri (2) , S. Ravets (2) , J. Bloch (2) , A. Amo (2) , L. Le Gratiet (2)

1 PhLAM - Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523
2 C2N - Centre de Nanosciences et de Nanotechnologies
3 LPS - Laboratoire de Physique des Solides

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.

Domaines: Physique [physics]; Systèmes mésoscopiques et effet Hall quantique [cond-mat.mes-hall]

B. Real, O. Jamadi, M. Milićević, N. Pernet, P. St-Jean, et al.. Semi-Dirac Transport and Anisotropic Localization in Polariton Honeycomb Lattices. Physical Review Letters, 2020, 125 (18), ⟨10.1103/PhysRevLett.125.186601⟩. ⟨hal-02988453⟩