Strain-Induced Trapping of Indirect Excitons in MoSe2/WSe2 Heterostructures
Strain-Induced Trapping of Indirect Excitons in MoSe2/WSe2 Heterostructures
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DOI：
10.1021/acsphotonics.0c00567
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发表时间：
2020-09-16
期刊：
影响因子：
7
通讯作者：
Ma, Xuedan
中科院分区：
文献类型：
--
作者：
Wang, Wei;Ma, Xuedan
了解和控制过渡金属二卤化物(TMD)材料中的激子对于探索TMD中丰富的多体物理及其在光电子学和光电子学中的应用具有重要意义。局域应变调制已被用作在TMD单分子膜中产生势阱和局域层内激子的有效方法。在这里，我们研究应变对TMD异质结中间接激子的影响。从应变中心出现的窄的光谱峰和它们急剧缩短的寿命表明，在异质结构中形成了潜在的陷阱，并在其中捕获了间接激子。这些被捕获的间接激子没有光子反聚束，进一步揭示了它们在势阱中的微弱局域化。我们的研究表明，与层内激子相比，由于间接激子的独特性质，获得高度局域的间接激子需要更窄的势垒。这些发现对于在TMD异质结构中创建长波量子发射体和探索TMD中的间接激子凝聚和运动具有重要的意义。
Understanding and control of excitons in transition metal dichalcogenide (TMD) materials are essential for the exploration of the rich many-body physics in TMDs and their applications in photonic and optoelectronic devices. Local strain modulation has been utilized as an effective approach for creating potential traps and localizing intralayer excitons in TMD monolayers. Here, we investigate the effect of strains on indirect excitons in TMD heterostructures. The emergence of narrow spectral peaks from the strained sites together with their drastically reduced lifetimes indicates the formation of potential traps in the heterostructures and the trapping of indirect excitons in them. The absence of photon-antibunching from these trapped indirect excitons further reveals their weak localization in the potential traps. Our study indicates that, compared to the case of intralayer excitons, narrower potential traps are required for obtaining highly localized indirect excitons due to their unique properties. These findings have important implications for creating long-wavelength quantum emitters in TMD heterostructures and the exploration of indirect exciton condensation and motion in TMDs.