Latini Simone, De Giovannini Umberto, Sie Edbert J, Gedik Nuh, Hübener Hannes, Rubio Angel
Max Planck Institute for the Structure and Dynamics of Matter and Center for Free Electron Laser Science, 22761 Hamburg, Germany.
Nano-Bio Spectroscopy Group, Departamento de Fisica de Materiales, Universidad del Pas Vasco UPV/EHU, 20018 San Sebastin, Spain.
Phys Rev Lett. 2021 Jun 4;126(22):227401. doi: 10.1103/PhysRevLett.126.227401.
A phonoriton is an elementary excitation that is predicted to emerge from hybridization between exciton, phonon, and photon. Besides the intriguing many-particle structure, phonoritons are of interest as they could serve as functional nodes in devices that utilize electronic, phononic, and photonic elements for energy conversion and thermal transport applications. Although phonoritons are predicted to emerge in an excitonic medium under intense electromagnetic wave irradiation, the stringent condition for their existence has eluded direct observation in solids. In particular, on-resonance, intense pumping schemes have been proposed, but excessive photoexcitation of carriers prevents optical detection. Here, we theoretically predict the appearance of phonoritonic features in monolayer hexagonal boron nitride (h-BN) embedded in an optical cavity. The coherent superposition nature of phonoriton states is evidenced by the hybridization of exciton-polariton branches with phonon replicas that is tunable by the cavity-matter coupling strength. This finding simultaneously provides an experimental pathway for observing the predicted phonoritons and opens a new avenue for tuning materials properties.
声子极化激元是一种基本激发，预计它将由激子、声子和光子之间的杂化产生。除了具有引人入胜的多粒子结构外，声子极化激元还备受关注，因为它们可以作为利用电子、声子和光子元件进行能量转换和热传输应用的器件中的功能节点。尽管预计声子极化激元会在强电磁波照射下的激子介质中出现，但它们存在的严格条件在固体中尚未得到直接观测。特别是，已经提出了共振、强泵浦方案，但载流子的过度光激发阻碍了光学检测。在这里，我们从理论上预测了嵌入光学腔中的单层六方氮化硼（h-BN）中声子极化激元特征的出现。激子极化激元分支与声子复制品的杂化证明了声子极化激元态的相干叠加性质，这种杂化可通过腔-物质耦合强度进行调节。这一发现同时为观测预测的声子极化激元提供了一条实验途径，并为调节材料特性开辟了一条新途径。
