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Interfacial anisotropic exciton-polariton manifolds in ReS$_2$

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 نشر من قبل Devarshi Chakrabarty
 تاريخ النشر 2021
  مجال البحث فيزياء
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Light-matter coupling in van der Waals materials holds significant promise in realizing Bosonic condensation and superfluidity. The underlying semiconductors crystal asymmetry, if any, can be utilized to form anisotropic half-light half-matter quasiparticles. We demonstrate generation of such highly anisotropic exciton-polaritons at the interface of a biaxial layered semiconductor, stacked on top of a distributed Bragg reflector. The spatially confined photonic mode in this geometry couples with polarized excitons and their Rydberg states, creating a system of highly anisotropic polariton manifolds, displaying vacuum Rabi splitting of upto 68 meV. Rotation of the incident beam polarization is used to tune coupling strength and smoothly switch regimes from weak to strong coupling, while also enabling transition from one three-body coupled oscillator system to another. Light-matter coupling is further tunable by varying the number of weakly coupled optically active layers. Our work provides a versatile method of engineering devices for applications in polarization-controlled polaritonics and optoelectronics.



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