报告题目：All-Inorganic Halide Perovskites for Light Emitting Applications

主讲人：张汉东博士

报告摘要

All-inorganic cesium lead halide perovskite nanostructures have attracted a great deal of attention in recent years. I will present our latest works on the characterization and light emitting applications of CsPbX3 (X=Cl, Br and I) nanocrystals. Low-threshold and ultrastable stimulated emission was demonstrated under atmospheric condition. The gain mechanism is attributed to biexcitonic recombination. The nonlinear optical properties including the multi-photon absorption and resultant photoluminescence of the CsPbX3nanocrystals were investigated. Especially, I will present the development of solution processable vertical cavity surface emitting lasers (VCSELs) from CsPbBr3 nanocrystals. VCSELs are an important class of laser devices that have been used in a broad range of applications like optical communication, high density optical storage, laser display, parallel optical computing and signal processing. However, most of the commercial VCSELs were developed from complicated epitaxial growth of semiconductor heterostructures of many layers in which both bandgap alignment and lattice mismatch are serious concerns. Hence, the cost of the ordinary VCSELs remains to be high. We realized an efficient VCSEL device from the all-inorganic cesium lead halide perovskite nanocrystals. The fabrication of VCSEL device relied on the all solution-based approach, which can significantly reduce the production cost. Moreover, the novel VCSEL no longer has to meet the stringent lattice matching requirement, which allows the independent adjustment of the cavity and the solution-processable nanocrystals for tunable lasers. We have demonstrated a low threshold, excellent spatial and temporal coherence, and favorable stability for the newly-engineered perovskite nanocrystal-based VCSELs, which is very promising for practical applications and represents a significant leap towards low cost yet high-performance laser devices.

报告时间：2018年5月23日下午16:30-17:30

报告地点：崇文楼B408

张汉东博士简历

孙汉东博士目前是新加坡南洋理工大学（NTU）物理与数学科学学院，物理与应用物理系副教授和（学术）副主任。他分别在大连理工大学，华中科技大学和香港科技大学获得物理学学士，光电硕士学位和物理学博士学位。曾担任日本RIKEN前沿研究系统研究员、英国斯特拉斯克莱德大学光子学研究所博士后研究员。他于2007年加入南洋理工大学担任助理教授，并自2013年3月起担任终身副教授。2016年，因对光子材料和结构研究领域的突出贡献，被选为美国物理学会会员（APS Fellow）。目前的研究领域主要涵盖了各类无机量子点、量子线、量子阱以及有机聚合物材料的生长，电子结构和激子动力表征和功能器件研究。

                                                         汽车与电子工程系

                                                         2018年5月22日