Department of Physics, Imperial College London, Prince Consort Road, London, SW7 2AZ, UK.
Department of Materials Science and Engineering, Stanford University, Stanford, CA, 94305, USA.
Nat Commun. 2023 May 11;14(1):2719. doi: 10.1038/s41467-023-38262-6.
Since Purcell's seminal report 75 years ago, electromagnetic resonators have been used to control light-matter interactions to make brighter radiation sources and unleash unprecedented control over quantum states of light and matter. Indeed, optical resonators such as microcavities and plasmonic antennas offer excellent control but only over a limited spectral range. Strategies to mutually tune and match emission and resonator frequency are often required, which is intricate and precludes the possibility of enhancing multiple transitions simultaneously. In this letter, we report a strong radiative emission rate enhancement of Er-ions across the telecommunications C-band in a single plasmonic waveguide based on the Purcell effect. Our gap waveguide uses a reverse nanofocusing approach to efficiently enhance, extract and guide emission from the nanoscale to a photonic waveguide while keeping plasmonic losses at a minimum. Remarkably, the large and broadband Purcell enhancement allows us to resolve Stark-split electric dipole transitions, which are typically only observed under cryogenic conditions. Simultaneous radiative emission enhancement of multiple quantum states is of great interest for photonic quantum networks and on-chip data communications.
自 75 年前 Purcell 的开创性报告以来，电磁谐振器已被用于控制光物质相互作用，以制造更亮的辐射源，并对光和物质的量子态进行前所未有的控制。事实上，诸如微腔和等离子体激元天线之类的光学谐振器提供了出色的控制，但仅在有限的光谱范围内。通常需要相互调整和匹配发射和谐振器频率的策略，这很复杂，并且排除了同时增强多个跃迁的可能性。在这封信中，我们报告了在基于 Purcell 效应的单个等离子体波导中，铒离子在整个电信 C 波段的强辐射发射速率增强。我们的间隙波导采用反向纳米聚焦方法，可有效地增强、提取和引导纳米级的发射，并将等离子体损耗保持在最低水平，同时引导至光子波导。值得注意的是，大的和宽带的 Purcell 增强允许我们分辨通常仅在低温条件下观察到的 Stark 分裂电偶极跃迁。多个量子态的同时辐射发射增强对于光子量子网络和片上数据通信具有重要意义。
