Dielectric nanoresonators and metasurfaces for photon pair generation

用于光子对生成的介电纳米谐振器和超表面

• 批准号: 407070005
• 负责人: Professor Dr. Thomas Pertsch
• 金额: --
• 依托单位: Institut für Angewandte Physik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/407070005?language=en
• 关键词: Dielectric; nanoresonators; metasurfaces; photon; pair

Dielectric optical nanoresonators and metasurfaces constructed from such nanoresonators have been shown to enable control of light scattering, reflection and transmission. In structures with second-order nonlinearity, efficient second-harmonic generation can be used to generate classical light, with properties depending on the nanoresonators' geometry. The project nanoPAIR investigates whether such control is also possible over the quantum properties of nonclassical light generated in dielectric nanoresonators and metasurfaces. Specifically, it will investigate how the spectrum, spatial distribution, polarization, and entanglement of photon pairs generated by spontaneous parametric down-conversion (SPDC) depend on substrate materials, geometry of the nanoresonators, and their arrangement in metasurfaces.The optical properties of dielectric nanoresonators are governed by localized resonances, which can be described as superposition of multipoles and which define the local field profiles and emission directions of photons involved in SPDC. Using the multipole description, a systematic understanding of possible classical properties of the generated photon pairs, i.e. their polarization, spectrum, and emission direction, will be established based on the geometric dimensions, asymmetries, and nonlinear properties of single nanoresonators.By combining several similar nanoresonators in metasurfaces, we aim to enhance the efficiency of SPDC and obtain additional tuning parameters, e.g. lattice period mediating coupling between the nanoresonators, lattice symmetry, and orientation of nanoresonators with respect to the metasurface lattice.Understanding how to use these parameters to control SPDC will unlock the full potential of nonlinear metasurfaces for quantum state generation. We aim to achieve effective orthogonality of control parameters with respect to their influence on the properties of the photon pairs in order to realize almost arbitrary combinations of their polarization, direction, and spectrum, needed by particular applications.Our investigations will comprise analytical modelling and rigorous simulations of SPDC in nanostructures, realization of nanoresonators and metasurfaces in Aluminum Gallium Arsenide and Lithium Niobate as well as experimental verification of discovered effects.With our research, we will enable the use of metasurfaces as sources for photon pairs with a large number of spatial modes, where the properties of each mode can be tuned independently. This is notably different from other quantum source concepts allowing the generation of spatially-multimode photon pairs, e.g. bulk crystals, where the fixed crystal properties determine the possible modes that can be used. Hence, metasurfaces are promising candidates as sources for quantum-optic applications relying on many spatial modes, as e.g. high-resolution quantum imaging or free-space quantum communication with entangled vortex beams.

电介质光学纳米谐振器和由这种纳米谐振器构成的超表面已被证明能够控制光的散射、反射和透射。在二阶非线性结构中，有效的二次谐波产生可用于产生经典光，其特性取决于纳米谐振器的几何形状。纳米空气项目研究了这种控制是否也可能对介电纳米谐振器和超表面中产生的非经典光的量子特性进行控制。具体来说，它将研究自发参数下转换（SPDC）产生的光子对的光谱、空间分布、极化和纠缠如何依赖于衬底材料、纳米谐振器的几何形状以及它们在超表面中的排列。介质纳米谐振器的光学特性受局域共振控制，局域共振可以描述为多极叠加，并定义了SPDC中光子的局域场分布和发射方向。利用多极描述，将基于单纳米谐振器的几何尺寸、不对称性和非线性特性，系统地理解所产生的光子对的可能的经典性质，即它们的极化、光谱和发射方向。通过在超表面上组合几个相似的纳米谐振器，我们的目标是提高SPDC的效率，并获得额外的调谐参数，如晶格周期调解纳米谐振器之间的耦合，晶格对称性和纳米谐振器相对于超表面晶格的取向。了解如何使用这些参数来控制SPDC将释放非线性超表面在量子态生成中的全部潜力。我们的目标是实现控制参数对光子对性质影响的有效正交性，以便实现特定应用所需的偏振、方向和光谱的几乎任意组合。我们的研究将包括SPDC在纳米结构中的分析建模和严格模拟，砷化铝镓和铌酸锂的纳米谐振器和超表面的实现，以及发现效应的实验验证。通过我们的研究，我们将能够使用超表面作为具有大量空间模式的光子对的源，其中每个模式的属性可以独立调谐。这与其他允许产生空间多模光子对的量子源概念明显不同，例如块状晶体，其中固定的晶体特性决定了可以使用的可能模式。因此，超表面是依赖于许多空间模式的量子光学应用的有希望的候选者，例如高分辨率量子成像或纠缠涡旋光束的自由空间量子通信。