利用磁性超材料控制偶极子自发辐射的研究

By using sub-wavelength size artificial structures, optical Metamaterials obtain strong magnetic response which can't be found in conventional atomic and molecular media. As a result, interesting optical properties, such as negative refractive index are realized. In the same way, artificial magnetic response can have an influence back on the atomic dipole transitions especially the magnetic ones，this will add an extra dimensionality in controlling the radiative decay rates. In this project, we will use the artificial magnetic metamaterials to control both both electric and magnetic dipole transitions in optical frequencies. We will first develop the corresponding theoretical and simulation tools. We will study the response of the metamaterials regarding the radiative decay rates at different levels of complexity, ranging from the individual artificial atoms to the whole magnetic metamaterial and negative index metamaterials. We will understand the interaction between the light, the metamaterials and the atoms placed near or inside the metamaterials, and conclude universal law followed by artificial magnetic resonance structures when they are controlling the magnetic dipole transitions. We will design realistic metamaterials that can be used to control the magnetic dipole transitions and the electric dipole transitions at the same time. By improve the micr-nano fabrication processing, we will fabricate the design and valid the theory prediction. These investigations will not only expose the interesting physics of metamaterials in controlling radiative decay rates but will also provide theory and technique support of developing quantum optical devices, such as efficient light sources and sensitive magnetic probes.

光学超材料利用亚波长的人工结构实现了传统材料不具有的磁共振，从而获得负折射率等新颖光学特性，更为控制偶极子特别是原本禁戒跃迁的磁偶极子的自发辐射增添了有效的途径。然而现有研究仅对这个方向进行初步的理论探索，无法获得磁共振控制偶极子自发辐射的普遍规律并指导进一步实验研究。在本项目中，我们将从理论和实验上系统的研究如何利用磁性超材料来控制电和磁偶极子的自发跃迁这个问题。通过开发相应的理论和模拟工具，研究不同复杂程度的人工结构对偶极子自发辐射率的影响，了解光、磁共振和其内部及附近的偶极子之间相互作用的机制，从而得到磁共振控制电、磁偶极子跃迁的普遍规律；基于此设计出同时控制电、磁偶极子跃迁的超材料；进一步优化微纳米制备技术，制备出超材料，对理论预言进行验证和演示。该研究不仅揭示超材料在控制原子辐射率上的有趣物理内涵，更为设计基于磁性超材料的量子光学器件，如高效光源和敏感磁探针等提供支持。

光学超材料利用亚波长的人工结构实现了传统材料不具有的磁共振，从而获得负折射率等新颖光学特性，更为控制偶极子特别是原本禁戒跃迁的磁偶极子的自发辐射增添了有效的途径。然而现有研究仅对这个方向进行初步的理论探索，无法获得磁共振控制偶极子自发辐射的普遍规律并指导进一步实验研究。在本项目中，我们从理论和实验上系统的研究如何利用磁性超材料来控制电和磁偶极子的自发跃迁这个问题。通过开发相应的理论和模拟工具，研究不同复杂程度的人工结构对偶极子自发辐射率的影响，发现利用具有磁响应的超材料能够对磁偶极子的跃迁进行直接的调控，进一步的了解光、磁共振和其内部及附近的偶极子之间相互作用的机制，从而得到磁共振控制电、磁偶极子跃迁的普遍规律；基于此设计出同时控制电、磁偶极子跃迁的超材料；进一步优化微纳米制备技术，制备出具有强磁响应的可见光波段的超材料，对理论的结果进行验证，实现第一个直接调控磁偶极子发光的超材料。该研究不仅揭示超材料在控制原子辐射率上的有趣物理内涵，更为设计基于磁性超材料的量子光学器件，如高效光源和敏感磁探针等提供支持。