Long carrier lifetime in faceted PbS quantum dot superlattice fabricated by sedimentation method
Long carrier lifetime in faceted PbS quantum dot superlattice fabricated by sedimentation method
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DOI：
10.7567/1347-4065/ab641b
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发表时间：
2020-04-01
影响因子：
1.5
通讯作者：
Watanabe, Sui
中科院分区：
文献类型：
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作者：
Mukai, Kohki;Kimura, Ryota;Watanabe, Sui
制备了胶体量子点（QD）超晶格薄膜，并研究了其原始光学性质。将多面PbS量子点沉积在金字塔微孔阵列模板和平面基底上制备薄膜。在形成薄膜后的光致发光光谱中观察到量子点的量子态发射发生了红移，表明中间波段载流子的量子约束减弱。QD超晶格薄膜在激发态处的发射衰减曲线呈双指数曲线。较长的寿命为几十纳秒，这是由于中间波段的载波离域造成的。在模板上制备的量子点薄膜的发射寿命是在平面基底上制备的量子点薄膜的发射寿命的两倍以上，这表明模板有助于形成大面积的量子点超晶格。(C) 2020日本应用物理学会
We fabricated colloidal quantum dot (QD) superlattice films and investigated their primal optical properties. The films were prepared by depositing faceted PbS QDs on pyramidal-microhole-array template and flat substrate in solution. The red shift in the quantum state emission of QDs was observed in photoluminescence spectra after film formation, which suggested the weakened quantum confinement of carriers in intermediate bands. Emission decay curves at the excited states in the QD superlattice film were double exponential. The longer lifetime was several tens of nanoseconds and attributed to the carrier delocalization in the intermediate bands. The emission lifetime of the QD film prepared on the template was found to be more than twice as long as that on the flat substrate, which suggested that the template helped to form large area QD superlattice. (C) 2020 The Japan Society of Applied Physics