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Semi-Dirac Transport and Anisotropic Localization in Polariton Honeycomb Lattices
B Real1, O Jamadi1, M Milićević2
1Univ. Lille, CNRS, UMR 8523-PhLAM-Physique des Lasers Atomes et Molécules, F-59000 Lille, France.
Physical Review Letters
|November 16, 2020
Summary
Compression creates a semi-Dirac cone in graphene, altering its properties. This study demonstrates anisotropic polariton transport and localization in a related lattice, revealing new physics of exotic Dirac dispersions.
Area of Science:
- Condensed matter physics
- Quantum mechanics
- Materials science
Background:
- Compression significantly alters graphene's electronic properties by modifying the Dirac cone symmetry.
- A critical compression can lead to a semi-Dirac cone, exhibiting unique directional electronic behavior.
Purpose of the Study:
- To provide direct evidence of anisotropic polariton transport in a lattice exhibiting a semi-Dirac cone.
- To investigate the localization properties of polaritons influenced by the semi-Dirac dispersion.
Main Methods:
- Fabrication of a honeycomb lattice using coupled micropillars to emulate a semi-Dirac cone.
- Optical induction of a vacancy-like defect within the lattice structure.
- Observation and analysis of polariton distribution and transport behavior.
Main Results:
- Demonstrated highly anisotropic transport of polaritons within the engineered lattice.
- Observed anisotropically localized polariton distribution in a single sublattice upon defect induction.
- Confirmed the influence of semi-Dirac dispersion on polariton localization.
Conclusions:
- The study provides direct experimental evidence for anisotropic polariton transport and localization in a semi-Dirac system.
- This work highlights the potential for controlling quantum phenomena in engineered lattices with exotic band structures.
- Opens new avenues for exploring transport and localization in systems with chiral symmetry and unique Dirac dispersions.
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