Generation, Detection and Light-Matter Interactions of Focused Doughnut Pulses

聚焦甜甜圈是麦克斯韦方程组的解，该方程组仅以电磁能在自由空间中以光速传播的短脉冲的形式存在。它们与横波的区别在于电磁场的环形配置和沿传播方向的沿着强场分量。除其他外，他们是非常重要的，因为类似的环形激励，这是广泛研究的光电研究中心的南安普顿大学在过去。由于它们在物质中产生的特殊激发，它们的产生可能为新的光谱方法开辟道路。在这个研究项目中，我们从理论和实验上研究它们的产生，检测和与物质的相互作用。在对它们的特性进行理论研究之后，我们试图了解它们的光学特性，以便在实验室中进行精确操作。它们的产生似乎可以通过宽带脉冲与适当设计的超颖表面相互作用来实现。一些脉冲表征技术将被应用，以测试和？重新调整他们这一代。最后，将设计轻物质相互作用实验，以激发环形模和动态Anapole。

Focused doughnuts are solutions to Maxwell's equations that exist only in the form of short burst of electromagnetic energy propagating in free-space at the speed of light. They are distinguished from transverse waves by a toroidal configuration of electromagnetic fields and strong field components along the propagation direction. Among others, they are of great importance because of the similarities with the toroidal excitations, that were studied extensively at the Optoelectronics Research Centre of the University of Southampton in the past. Their generation could open the way for new spectroscopic methods, due to the peculiar excitations that they create in matter. In this research project we study, theoretically and experimentally, their generation, detection and interaction with matter. After a theoretical examination of their characteristics, we seek to understand their optical properties for precise manipulation in the laboratory. Their generation seems to be possible via a broadband pulse interaction with a properly engineered metasurface. A number of pulse characterization techniques will be applied in order to test and ?re-tune their generation. Finally, light matter interaction experiments for the excitation of toroidal modes and dynamic anapoles will be designed.