Chemically synthesized near-infrared to mid-infrared (IR) colloidal quantum dots (QDs) offer a promising platform for the realization of devices including emitters, detectors, security, and sensor systems. However, at longer wavelengths, the quantum yield of such QDs decreases as the radiative emission rate drops following Fermi’s golden rule, while non-radiative recombination channels compete with light emission. Control over the radiative and non-radiative channels of the IR-emitting QDs is crucially important to improve the performance of IR-range devices. Here, we demonstrate strong enhancement of the spontaneous emission rate of near- to mid-IR HgTe QDs coupled to periodically arranged plasmonic nanoantennas, in the form of nanobumps, produced on the surface of glass-supported Au films via ablation-free direct femtosecond laser printing. The enhancement is achieved by simultaneous radiative coupling of the emission that spectrally matches the first-order lattice resonance of the arrays, as well as more efficient photoluminescence excitation provided by coupling of the pump radiation to the local surface plasmon resonances of the isolated nanoantennas. Moreover, coupling of the HgTe QDs to the lattice plasmons reduces the influence of non-radiative decay losses mediated by the formation of polarons formed between QD surface-trapped carriers and the IR absorption bands of dodecanethiol used as a ligand on the QDs, allowing us to improve the shape of the emission spectrum through a reduction in the spectral dip related to this ligand coupling. Considering the ease of the chemical synthesis and processing of the HgTe QDs combined with the scalability of the direct laser fabrication of nanoantennas with tailored plasmonic responses, our results provide an important step towards the design of IR-range devices for various applications.

化学合成的近红外到中红外 (IR) 胶体量子点 (QD) 为实现包括发射器、检测器、安全和传感器系统在内的设备提供了一个有前景的平台。然而，在更长的波长下，这种量子点的量子产率随着辐射发射率的下降而下降，遵循费米黄金法则，而非辐射复合通道与光发射竞争。控制红外发射量子点的辐射和非辐射通道对于提高红外范围器件的性能至关重要。在这里，我们展示了通过无烧蚀直接飞秒激光在玻璃支撑的金膜表面上产生的以纳米凸块形式耦合到周期性排列的等离子体纳米天线的近至中红外 HgTe 量子点的自发发射率的强烈增强印刷。这种增强是通过光谱上与阵列的一阶晶格共振相匹配的发射的同时辐射耦合，以及通过将泵浦辐射耦合到孤立的纳米天线的局部表面等离子体共振而提供的更有效的光致发光激发来实现的。此外，HgTe QD 与晶格等离子体的耦合减少了由 QD 表面捕获的载流子和用作 QD 上的配体的十二硫醇的 IR 吸收带之间形成的极化子介导的非辐射衰变损失的影响，使我们能够通过减少与该配体耦合相关的光谱倾角来改善发射光谱的形状。