AI 中文总结
该研究将TMD与飞秒激光写入的表面波导结合，通过低温光谱装置观测到A激子的光谱变化，归因于波导模式与激子的强耦合，形成传播型激子极化激元，为相关研究提供了适应性实验平台。
AI 中文摘要
将少层材料集成到光子电路中是新型片上光子应用的一个有前景的概念。我们将过渡金属二硫化物（transition metal dichalcogenides, TMDs）与飞秒激光写入的表面波导相结合，该波导嵌入熔融石英芯片中。我们的新型低温光学光谱装置能够耦合到波导，并同时从顶部聚焦到TMD层，以在多种测量几何结构中实现微光致发光（micro-photoluminescence, μPL）信号的差异化激发与收集。基于此，当捕获通过波导传播的μPL信号时，我们观察到封装TMD单层的A激子发生光谱变化。根据六方氮化硼（hexagonal boron nitride, hBN）封装层的厚度，这些变化表现为A激子的能量红移，甚至分裂为两个组分。我们将该行为归因于波导模式与样品中激子的强耦合，从而形成传播型激子极化激元。通过采用传输矩阵法对激子附近的平板波导简化模型进行计算，为我们的解释提供了支持。该实验平台已被证明是研究传播型极化激元的高度适应性框架，同样有望在集成光子电路中利用激子极化激元的独特性质。
英文摘要
Integrating few-layer materials into photonic circuits is a promising concept for novel on-chip photonic applications. We incorporate transition metal dichalcogenides (TMDs) with femtosecond-laser-written surface waveguides, which are embedded in fused silica chips. Our novel low-temperature optical spectroscopy setup enables coupling to the waveguide and simultaneous focus from the top to the TMD layer for a distinct excitation and collection of micro-photoluminescence ($μ$PL) signals in several measurement geometries. Along these lines, we observe spectral changes of the A exciton for encapsulated TMD monolayers when capturing the $μ$PL signal propagating through the waveguide. Depending on the thickness of the encapsulation with hexagonal boron nitride (hBN), these changes manifest as energetic redshifts of the A exciton, or even a splitting of the A exciton into two components. We attribute this behavior to strong coupling of the waveguide mode and the exciton in the sample, giving rise to the formation of propagating exciton-polaritons. Our interpretation is supported by calculations for a simplified model of a slab waveguide in the vicinity of an exciton by using the transfer matrix method. Having proven to be a highly adaptable framework for the study of propagating polaritons, our experimental platform likewise holds great promise for harnessing the unique properties of exciton-polaristons in integrated photonic circuits.
