Exciton Polaritons in Halide Perovskite Microcavities

Online Physics Seminar by Dr. Su Rui (Nanyang Technological University), held on 9 Feb 2022.

Abstract:
Exciton polaritons are part-light, part-matter Bosonic quasiparticles with strong interacting nature, by dressing excitonic resonances with microcavity photons. They inherit the advantages from their excitonic and photonic components, such as extremely light effective mass and strong nonlinearity, serving as a linking bridge between photonics and condensed matter. These advantages provide them tremendous potential in quantum fluid of light (i.e., Bose-Einstein condensation of polaritons), ultrafast polaritonic logic circuits and topological quantum matter. In this talk, I will introduce our progress in realizing exciton polaritons and their condensation in halide perovskite microcavities at room temperature [1,2]. Due to the non-equilibrium nature, polariton condensates can occur at nonground states, showing long-range propagation with high group velocity [3]. These polariton states can be further manipulated by periodic trapping potentials to emulate electron Hamiltonians, which shows a large forbidden bandgap opening up to 13 meV [4]. Finally, by introducing a lattice potential that emulates 1D Su-Schrieffer-Heeger Hamiltonian, topologically nontrivial phase of polaritons can be realized in a perovskite lattice, where the topological phase can be tuned by means of polarization control [5].

References:
[1] R. Su et al. Nano Lett. 17, 3982–3988 (2017). [2] J. Wu et al. Nano Lett. 21, 3120–3126 (2021), [3] R. Su et al. Sci. Adv. 4, eaau0244 (2018), [4] R. Su et al. Nature Phys. 16, 301–306 (2020), [5] R. Su et al. Sci. Adv. 7, eabf8049 (2021)