報告題目：Nonlinear phenomena in polariton topological insulators

報告人：Yaroslav Kartashov教授

報告時間：11月13日（周二）16:00

報告地點：理科樓440

科技處 前沿院 文理學院

2018年11月6日

報告人簡介：

Yaroslav Kartashov 教授是俄羅斯科學院光譜研究所理論系的首席科學家，同時也是巴塞羅那光子科學研究所(ICFO-The Institute of Photonics Sciences)的客座教授。年僅42歲，但已經在光學和物理學主流刊物上發表了260多篇，包括二十多篇Physics Review Letters, 并在物理系上頂尖期刊如Reviews of Modern Physics (IF 36.367), Progress in Physics (IF 14.257) 發表了多篇Review性質的文章。是非線性光學和拓撲光子學領域內非常著名的專家和具有重要影響力的學者，是Optics Letters期刊非線性光學方向的編輯，也是OSA主辦的Nonlinear Photonics歷年年會的總主席和眾多具有國際重要影響力的會議的組織者。

報告摘要：

Nonlinear phenomena in polariton topological insulators

In this presentation I will address unique system allowing investigation of the interplay between nonlinearity and topology - polariton condensates in optical microcavities. Optical microcavities supporting exciton-polariton quasi-particles offer one of the most powerful platforms for the investigation of rapidly developing area of topological photonics in general, and of photonic topological insulators in particular. Energy bands of polaritons in arrays of microcavity pillars arranged into various lattice configurations, such as honeycomb or Lieb, are readily controlled by the magnetic field and strongly influenced by the spin-orbit coupling effects, a combination leading to formation of unidirectional edge states in polariton topological insulators. In this presentation I will depart from the linear limit of non-interacting polaritons and address properties of nonlinear topological edge states, describe their instabilities resulting in the formation of localized topological quasi-solitons, which are exceptionally robust and immune to backscattering wavepackets propagating along the edge of the array of microcavity pillars. Both bright and dark topological quasi-solitons will be considered. I will also discuss bistability effects appearing in resonantly pumped polariton condensates in dissipative structured microcavities and describe how polarization and frequency of the pump beam may be used to control stability and localization of the excited nonlinear edge states that can be completely stable in such nonlinear "driven" systems. Finally, a variety of resonant phenomena with topological edge states that can be induced by temporal modulations of the underlying lattice of microcavity pillars will be discussed.