Engineering Directionality in Quantum Dot Shell Lasing Using Plasmonic Lattices
Engineering Directionality in Quantum Dot Shell Lasing Using Plasmonic Lattices
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DOI：
10.1021/acs.nanolett.9b05342
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发表时间：
2020-02-01
期刊：
影响因子：
10.8
通讯作者：
Odom, Teri W.
中科院分区：
文献类型：
--
作者：
Guan, Jun;Sagar, Laxmi Kishore;Odom, Teri W.
我们报告了如何通过利用等离子体纳米粒子（NP）晶格中的高对称点来设计量子点（QD）激光的方向。纳米激光器结构由共形涂覆在二维方形 Ag NP 阵列上的 CdSe-CdS 核壳 QD 层组成。使用布里渊区 Delta 点附近的波导表面晶格共振 (W-SLR) 作为光学反馈，我们通过 CdS 壳中的增益以非法线发射角实现了激光发射。改变等离子体晶格的周期性使得晶格的其他高对称点（Gamma 或 M）与 QD 壳层发射重叠，这有利于激光方向的调谐。我们还增加了 QD 层的厚度，以引入更高阶的 W-SLR 模式，并避免能带结构中的交叉，从而扩大了任何所需激光发射角度的腔模式的选择。
We report how the direction of quantum dot (QD) lasing can be engineered by exploiting high-symmetry points in plasmonic nanoparticle (NP) lattices. The nanolaser architecture consists of CdSe-CdS core-shell QD layers conformally coated on two-dimensional square arrays of Ag NPs. Using waveguide-surface lattice resonances (W-SLRs) near the Delta point in the Brillouin zone as optical feedback, we achieved lasing from the gain in CdS shells at off-normal emission angles. Changing the periodicity of the plasmonic lattices enables other high-symmetry points (Gamma or M) of the lattice to overlap with the QD shell emission, which facilitates tuning of the lasing direction. We also increased the thickness of the QD layer to introduce higher-order W-SLR modes with additional avoided crossings in the band structure, which expands the selection of cavity modes for any desired lasing emission angle.