Bylinkin Andrei, Calavalle Francesco, Barra-Burillo María, Kirtaev Roman V, Nikulina Elizaveta, Modin Evgeny, Janzen Eli, Edgar James H, Casanova Fèlix, Hueso Luis E, Volkov Valentyn S, Vavassori Paolo, Aharonovich Igor, Alonso-Gonzalez Pablo, Hillenbrand Rainer, Nikitin Alexey Y
CIC nanoGUNE BRTA, Donostia - San Sebastian 20018, Spain.
Donostia International Physics Center (DIPC), Donostia - San Sebastián 20018, Spain.
Nano Lett. 2023 May 10;23(9):3985-3993. doi: 10.1021/acs.nanolett.3c00768. Epub 2023 Apr 28.
Strong coupling (SC) between light and matter excitations bears intriguing potential for manipulating material properties. Typically, SC has been achieved between mid-infrared (mid-IR) light and molecular vibrations or between visible light and excitons. However, simultaneously achieving SC in both frequency bands remains unexplored. Here, we introduce polaritonic nanoresonators (formed by h-BN layers on Al ribbons) hosting surface plasmon polaritons (SPPs) at visible frequencies and phonon polaritons (PhPs) at mid-IR frequencies, which simultaneously couple to excitons and molecular vibrations in an adjacent layer of CoPc molecules, respectively. Employing near-field optical nanoscopy, we demonstrate the colocalization of near fields at both visible and mid-IR frequencies. Far-field transmission spectroscopy of the nanoresonator structure covered with a layer of CoPc molecules shows clear mode splittings in both frequency ranges, revealing simultaneous SPP-exciton and PhP-vibron coupling. Dual-band SC may offer potential for manipulating coupling between exciton and molecular vibration in future optoelectronics, nanophotonics, and quantum information applications.
光与物质激发之间的强耦合（SC）在操纵材料特性方面具有引人入胜的潜力。通常，强耦合是在中红外（mid-IR）光与分子振动之间或可见光与激子之间实现的。然而，在两个频段同时实现强耦合仍未得到探索。在这里，我们引入了极化激元纳米谐振器（由铝带上的六方氮化硼（h-BN）层形成），其在可见光频率下承载表面等离激元极化子（SPPs），在中红外频率下承载声子极化子（PhPs），它们分别同时与相邻层的钴酞菁（CoPc）分子中的激子和分子振动耦合。利用近场光学纳米显微镜，我们展示了可见光和中红外频率下近场的共定位。覆盖有一层CoPc分子的纳米谐振器结构的远场透射光谱在两个频率范围内都显示出明显的模式分裂，揭示了同时存在的表面等离激元极化子 - 激子和声子极化子 - 振子耦合。双频段强耦合可能为未来的光电子学、纳米光子学和量子信息应用中操纵激子与分子振动之间的耦合提供潜力。
