【学术报告】陈子亭:Some new fomns of magnetic photonic crystals
In this talk we will introduce the concept of photonic alloys as non-periodic topological materials.

In this talk we will introduce the concept of photonic alloys as non-periodic topological materials.
如何在多界面复杂环境中对极化激元的性能实现多维、高效和精准调控是目前领域内面临的关键科学问题。为此,我们依托石墨烯表面等离激元与α相三氧化钼声子极化激元体系开展研究。利用极化激元的模式杂化耦合效应并结合功能天线设计、介电环境优化、范德华异质堆垛等材料与结构设计方法,实现了极化激元波长高效压缩、空间等频轮廓拓扑转变以及传输方向控制等功能。以此为基础,进一步构筑了面内双曲聚焦、无衍射传输透镜以及电可调负折射等纳米尺度光功能器件,展示了极化激元在纳米尺度的光操控能力。
Terahertz (THz) radiation, which is electromagnetic radiation in a frequency interval from 0.3 to 10 THz (1 mm – 30 μm wavelength), is the frontier in science and technology. Historically, THz technologies were used mainly within the astronomy community for studying the background of cosmic far-infrared radiation, and by the laser-fusion community for the diagnostics of plasmas.
In this lecture, I'll introduce photoemission spectroscopy and its applications in quantum materials research. The lecture begins with an introduction to electronic band structure, the basic working principles of photoemission spectroscopy, and its early use in material research. Later, I'll present state-of-the-art photoemission equipment and recent studies using these tools. The goal of this lecture is to provide a comprehensive overview of photoemission spectroscopy in condensed matter physics.
This lecture will review the recent progress in investigating a spontaneous build-up of macroscopic coherence in non-resonantly pumped semiconductor microcavities. Because of the strong interaction between excitons and cavity mode, the hybrid particles called polaritons appear. Inheriting high mobility and strong interactions from their constituents, these particles demonstrate superfluid behavior accompanied by spontaneous nucleation of vortices. I will describe experimental approaches for creation and manipulation of such peculiar structures including spatial confinement techniques. In addition, I will present a theoretical framework capable of explaining a number of recent experimental findings.
This lecture will provide an introductory overview of optical spectroscopy techniques and their applications in the study of two-dimensional (2D) quantum materials. As the field of 2D materials has rapidly expanded, understanding their unique optical and electronic properties has become important for advancing quantum science. We will begin with a basic review of key concepts in linear and nonlinear optical spectroscopies. Participants will gain insights into recent breakthroughs in the field, including moiré excitons and twist angle dependent tunable optical properties in twisted semiconducting bilayers. This session is designed for undergraduate students who are new to the field of 2D quantum materials and seek a comprehensive introduction to the application of optical spectroscopy in this cutting-edge area of research.
传统的超材料由于其在基板上的平面几何形状以及形成后无法定制响应而面临局限性。本次报告将通过以下几个方面介绍课题组最近在克服此类限制、探索新型“软”超材料研究中取得的进展:首先,通过利用热力学和光学对称性之间的交互作用,实现了非结构对称的超材料自组装单元结构;此外,将讨论如何使用软超材料来实现由量子真空涨落产生的长期寻求的卡西米尔量子平衡;以及通过利用这种基本相互作用,进一步讨论最近首次实现的超越衍射极限的卡西米尔双曲超材料以及在生物成像方面的应用。