题 目：Some New Insights From The Very old Electromagnetic Field Equations
报告人：陈子亭 教授（香港科技大学）
时 间：11月23日（周二），下午3：30
地 点：瑞安楼二楼报告厅
Abstract：
The Maxwell equations have been discovered for more than a century, and it is commonly believed that we know everything about these equations. The fact is quite the contrary. There are some implications of the Maxwell equations that are still unknown or controversial until very recently. For example, can an object be made invisible to EM waves? This question was answered only in 2006 when a new technique called “transformation optics” was introduced. I will briefly introduce this method, which establishes a correspondence between coordinate transformation and material parameters. Using this technique, a new class of graded refractive index materials with anisotropic and position-dependent properties can be designed to guide or manipulate light and wave in almost any way we wish, including steering light around an object to make it invisible. We will show that some special materials designed by transformation optics mappings can lead to optical illusion effects. For example, we can design a conceptual device that can optically transform one object into another object in a specified frequency.
In addition, we will try to answer the question “Can light attract"? Light carries momentum and the momentum transfer to an object pushes the object. This is the familiar textbook concept of photon pressure. We will show that under special circumstances, light interacting with “metamaterials” can induce a negative photon pressure, or in order words light can pull instead of push.
陈子亭博士：香港科技大学物理系首席教授，高技术研究所所长，1992年获美国能源部杰出科学贡献奖，美国物理学会理事，电磁科学院理事，Croucher Senior Research Fellow，海外杰出青年。长期从事第一性计算、纳米材料设计模拟计算、光子及声子晶体、电磁和声学左手材料等方面的研究工作，在第一性计算理论、光子晶体计算、准周期光子晶体、等效介质理论、声学Metamaterial的设计和研制等方面均有重要贡献，近期在转换光学和隐形衣研究方面有诸多原创性，提出互补介质和幻想光学等新概念、建立并完善了光学黑洞的理论模型。上述系列工作在Science、Nature、PRL、Advanced Materials等国际核心学术刊物上发表并被广为报道和引用。
