Luo Weijun, Puretzky Alexander, Lawrie Benjamin, Tan Qishuo, Gao Hongze, Swan Anna K, Liang Liangbo, Ling Xi
Department of Chemistry, Boston University, Boston, Massachusetts 02215, United States.
Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States.
Nano Lett. 2023 Nov 8;23(21):9740-9747. doi: 10.1021/acs.nanolett.3c02308. Epub 2023 Oct 25.
Exciton localization through nanoscale strain has been used to create highly efficient single-photon emitters (SPEs) in 2D materials. However, the strong Coulomb interactions between excitons can lead to nonradiative recombination through exciton-exciton annihilation, negatively impacting SPE performance. Here, we investigate the effect of Coulomb interactions on the brightness, single photon purity, and operating temperatures of strain-localized GaSe SPEs by using electrostatic doping. By gating GaSe to the charge neutrality point, the exciton-exciton annihilation nonradiative pathway is suppressed, leading to ∼60% improvement of emission intensity and an enhancement of the single photon purity (0) from 0.55 to 0.28. The operating temperature also increased from 4.5 K to 85 K consequently. This research provides insight into many-body interactions in excitons confined by nanoscale strain and lays the groundwork for the optimization of SPEs for optoelectronics and quantum photonics.
通过纳米级应变实现的激子局域化已被用于在二维材料中创建高效的单光子发射器（SPE）。然而，激子之间强烈的库仑相互作用会通过激子 - 激子湮灭导致非辐射复合，对SPE性能产生负面影响。在此，我们通过使用静电掺杂来研究库仑相互作用对应变局域化的GaSe单光子发射器的亮度、单光子纯度和工作温度的影响。通过将GaSe栅极调节到电荷中性点，抑制了激子 - 激子湮灭的非辐射途径，导致发射强度提高约60%，并且单光子纯度（0）从0.55提高到0.28。工作温度也相应地从4.5 K提高到85 K。这项研究为受纳米级应变限制的激子中的多体相互作用提供了见解，并为优化用于光电子学和量子光子学的单光子发射器奠定了基础。
