Control of excitons in transition metal dichalcogenides (TMDCs) and their heterostructures is fundamentally interesting for tailoring light-matter interactions and exploring their potential applications in high-efficiency optoelectronic and nonlinear photonic devices. While both intra- and interlayer excitons in TMDCs have been heavily studied, their behavior in the quantum tunneling regime, in which the TMDC or its heterostructure is optically excited and concurrently serves as a tunnel junction barrier, remains unexplored. Here, using the degree of freedom of a metallic probe in an atomic force microscope, we investigated both intralayer and interlayer excitons dynamics in TMDC heterobilayers via locally controlled junction current in a finely tuned sub-nanometer tip-sample cavity. Our tip-enhanced photoluminescence measurements reveal a significantly different exciton-quantum plasmon coupling for intralayer and interlayer excitons due to different orientation of the dipoles of the respective e-h pairs. Using a steady-state rate equation fit, we extracted field gradients, radiative and nonradiative relaxation rates for excitons in the quantum tunneling regime with and without junction current. Our results show that tip-induced radiative (nonradiative) relaxation of intralayer (interlayer) excitons becomes dominant in the quantum tunneling regime due to the Purcell effect. These findings have important implications for near-field probing of excitonic materials in the strong-coupling regime.

控制过渡金属二硫属化物（TMDC）及其异质结构中的激子对于定制光与物质相互作用并探索其在高效光电和非线性光子器件中的潜在应用具有根本意义。虽然 TMDC 中的层内和层间激子都已得到深入研究，但它们在量子隧道机制中的行为（其中 TMDC 或其异质结构受到光激发并同时充当隧道结势垒）仍未得到探索。在这里，我们利用原子力显微镜中金属探针的自由度，通过精细调谐的亚纳米尖端样品腔中的局部控制结电流，研究了 TMDC 异质双层中的层内和层间激子动力学。e - h对。使用稳态速率方程拟合，我们提取了有和没有结电流的量子隧道状态中激子的场梯度、辐射和非辐射弛豫率。我们的结果表明，由于珀塞尔效应，尖端诱导的层内（层间）激子的辐射（非辐射）弛豫在量子隧道机制中占据主导地位。这些发现对于强耦合状态下激子材料的近场探测具有重要意义。