论文标题
在范德华异质结构中的耦合层间激子与耳语画廊模式
Coupling interlayer excitons to whispering gallery modes in van der Waals heterostructures
论文作者
论文摘要
从二维材料组装的范德华异质结构为具有所需的光电特性的工程师结构提供了有希望的平台。在这里，我们使用由六角硼（H-BN）制成的波导耦合磁盘谐振器，以证明来自两个单一单层过渡金属二核苷的异质分子的层中激素的腔耦合发射。我们将摩西$ _ {\ rm 2} $ - wse $ _ {\ rm 2} $ HeteroBilayer夹在H-BN的两个平板之间，并将结果堆叠直接在波导耦合磁盘谐振器中直接将其堆叠。这使我们能够将活性材料定位在最高光场强度的区域中，从而最大化模式重叠和耦合强度。由于层间激子发射能低于单个单层的光条间隙，并且层间过渡本身具有较弱的振荡器强度，因此循环光仅被薄弱地重新吸收，从而导致不受影响的质量因子。我们的设备是完全波导耦合的，代表了片上范德华光子学的有前途的平台。
Van der Waals heterostructures assembled from two-dimensional materials offer a promising platform to engineer structures with desired optoelectronic characteristics. Here we use waveguide-coupled disk resonators made of hexagonal boron nitride (h-BN) to demonstrate cavity-coupled emission from interlayer excitons of a heterobilayer of two monolayer transition metal dichalcogonides. We sandwich a MoSe$_{\rm 2}$ - WSe$_{\rm 2}$ heterobilayer between two slabs of h-BN and directly pattern the resulting stack into waveguide-coupled disk resonators. This enables us to position the active materials into regions of highest optical field intensity, thereby maximizing the mode overlap and the coupling strength. Since the interlayer exciton emission energy is lower than the optical band gaps of the individual monolayers and since the interlayer transition itself has a weak oscillator strength, the circulating light is only weakly reabsorbed, which results in an unaffected quality factor. Our devices are fully waveguide-coupled and represent a promising platform for on-chip van der Waals photonics.
