Park Kyoung-Duck, May Molly A, Leng Haixu, Wang Jiarong, Kropp Jaron A, Gougousi Theodosia, Pelton Matthew, Raschke Markus B
Department of Physics, Department of Chemistry, and JILA, University of Colorado, Boulder, CO 80309, USA.
Department of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Korea.
Sci Adv. 2019 Jul 12;5(7):eaav5931. doi: 10.1126/sciadv.aav5931. eCollection 2019 Jul.
Optical cavities can enhance and control light-matter interactions. This level of control has recently been extended to the nanoscale with single emitter strong coupling even at room temperature using plasmonic nanostructures. However, emitters in static geometries, limit the ability to tune the coupling strength or to couple different emitters to the same cavity. Here, we present tip-enhanced strong coupling (TESC) with a nanocavity formed between a scanning plasmonic antenna tip and the substrate. By reversibly and dynamically addressing single quantum dots, we observe mode splitting up to 160 meV and anticrossing over a detuning range of ~100 meV, and with subnanometer precision over the deep subdiffraction-limited mode volume. Thus, TESC enables previously inaccessible control over emitter-nanocavity coupling and mode volume based on near-field microscopy. This opens pathways to induce, probe, and control single-emitter plasmon hybrid quantum states for applications from optoelectronics to quantum information science at room temperature.
光学腔可以增强并控制光与物质的相互作用。近来，借助等离子体纳米结构，即使在室温下，这种控制水平也已扩展到单发射器强耦合的纳米尺度。然而，处于静态几何结构中的发射器限制了调节耦合强度或将不同发射器耦合到同一腔的能力。在此，我们展示了一种在扫描等离子体天线尖端与衬底之间形成的纳米腔的尖端增强强耦合（TESC）。通过可逆且动态地寻址单个量子点，我们观察到高达160毫电子伏特的模式分裂以及在约100毫电子伏特失谐范围内的反交叉，并且在深度亚衍射极限模式体积上具有亚纳米精度。因此，TESC能够基于近场显微镜对发射器 - 纳米腔耦合和模式体积进行前所未有的控制。这为在室温下诱导、探测和控制单发射器等离子体混合量子态开辟了道路，这些应用涵盖从光电子学到量子信息科学等领域。
