Atom-Light Interaction in High-Pressure Optical Waveguides

高压光波导中的原子光相互作用

• 批准号: 52015807
• 负责人: Professor Dr. Martin Weitz
• 金额: --
• 依托单位: Institut für Angewandte Physik
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2007
• 资助国家: 德国
• 起止时间: 2006-12-31 至 2010-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/52015807?language=en
• 关键词: Atom; Light; Interaction; Pressure; Optical

The aim of this project is the study of nonlinear optics and collective photonic quantum effects with light confined in optical hollow core waveguides filled with an atomic gas. A buffer gas pressure of several hundreds of bars leads to a wide pressure-broadened bandwidth of the system, interpolating between the usual sharp atomic physics spectral lines and the band structure of solid state physics systems.In previous works, we have demonstrated atomic spectroscopy on a rubidium cell filled with 500 bar of argon and helium buffer gas, respectively. Pressure and saturation broadening in a tightly focused optical beam geometry leads to a spectral bandwidth of tens of nanometers. The room temperature linewidth of the well controlled quantum optical system in energy units approaches the thermal energy, and we have observed evidence for thermal equilibrium of the strongly coupled dressed state (coupled atom-light Eigenstate) system. While our interaction length is presently limited by the spatial depth of the Gaussian focus of the driving light beam, we expect that with appropriate light confinement in a waveguide the optically dense regime can be reached, allowing for novel, high bandwidth nonlinear optical systems and collective photonic quantum effects. Taking advantage of the existing expertise of the Bonn focused Research Unit, we plan to investigate both hollow core photonic crystal fibers and metallic waveguides. The latter ones are well-developed for the mid-infrared spectral region, but the fabrication and the exploration of plasmon-induced effects of metal waveguides in the optical regime are an active field of research. Clearly, a considerable further increase of the interaction length is possible with gas-filled hollow core photonic crystal fibres, which will be studied subsequently within the program.We expect to demonstrate wideband frequency mixing, taking advantage of the possible exponential suppression of absorption in the pressure broadened waveguide system. The increased interaction length in a resonantly pumped sample allows for intriguing thermal equilibrium photonic quantum effects, as a Bose-Einstein-like phase transition of polaritons (i.e. coupled hybrid atom-light quasiparticles) between a thermal state and a condensed, ordered polariton state. An intriguing perspective of such densely filled optical waveguides, interpolating between usual gas phase and solid state conditions, lies in the exploration of novel ways to tailor the state of light.

该项目的目的是研究非线性光学和集体光子量子效应，其中光被限制在充满原子气体的光学空心波导中。数百巴的缓冲气体压力导致系统具有较宽的压力展宽带宽，插值在通常的尖锐原子物理谱线和固态物理系统的能带结构之间。在之前的工作中，我们已经在分别填充有 500 巴的氩气和氦气缓冲气体的铷池上演示了原子光谱。紧密聚焦的光束几何形状中的压力和饱和度加宽导致光谱带宽达到数十纳米。良好控制的量子光学系统的室温线宽以能量单位接近热能，并且我们观察到强耦合修饰态（耦合原子光本征态）系统热平衡的证据。虽然我们的相互作用长度目前受到驱动光束高斯焦点的空间深度的限制，但我们期望通过在波导中适当的光限制，可以达到光学密集状态，从而允许新颖的高带宽非线性光学系统和集体光子量子效应。利用波恩重点研究单位的现有专业知识，我们计划研究空心光子晶体光纤和金属波导。后者在中红外光谱区域得到了很好的发展，但光学领域金属波导的等离激元诱导效应的制造和探索是一个活跃的研究领域。显然，使用充气空芯光子晶体光纤可以进一步显着增加相互作用长度，这将在该计划中进行后续研究。我们期望利用压力展宽波导系统中可能的指数抑制吸收来演示宽带混频。共振泵浦样品中增加的相互作用长度允许产生有趣的热平衡光子量子效应，作为热态和凝聚、有序极化子状态之间极化子（即耦合混合原子光准粒子）的类玻色-爱因斯坦相变。这种密集填充的光波导的一个有趣的观点是在通常的气相和固态条件之间进行插值，在于探索定制光状态的新方法。