研究目的
Investigating the effect of indium alloying on the charge carrier dynamics of thick-shell InP/ZnSe quantum dots to understand their photophysical properties and potential for improving photoluminescence quantum yield.
研究成果
The study reveals that both alloy and core/shell InP/ZnSe QDs exhibit extensive charge carrier trapping, with more extensive trapping observed in the alloy nanocrystals. Despite the thick-shell architecture, structural defects still limit radiative recombination. Minimizing indium alloying is suggested to improve the QDs' optical properties.
研究不足
Structural defects caused by III–V/II–VI charge carrier imbalances in the QDs limit the photoluminescence quantum yield. The study suggests that minimizing alloying and growing an outer layer of a wider bandgap material could be important next steps.
1：Experimental Design and Method Selection:
The study involved synthesizing thick-shell InP/ZnSe QDs with two distinct interfaces (alloy and core/shell) and characterizing their structural and optical properties. Ultrafast fluorescence upconversion spectroscopy was used to probe charge carrier dynamics.
2：Sample Selection and Data Sources:
Two QD samples were prepared with similar InP starting cores but different shell compositions (alloy and core/shell).
3：List of Experimental Equipment and Materials:
High-resolution energy-dispersive x-ray spectroscopy scanning transmission electron microscopy (STEM-EDS) for structural characterization, and a femtosecond laser system for ultrafast fluorescence upconversion spectroscopy.
4：Experimental Procedures and Operational Workflow:
Synthesis of QDs, structural characterization using STEM-EDS, and optical characterization using ultrafast fluorescence upconversion spectroscopy.
5：Data Analysis Methods:
The ultrafast fluorescence upconversion spectra were fit using a convolution of a Gaussian laser pulse with exponential decays to represent various decay pathways.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容-
Mira 900 Basic
900 Basic
Coherent
Mode-locked Ti:sapphire oscillator seeded by the Verdi V18.
-
RegA 9000
9000
Coherent
Regenerative amplifier seeded by the Mira 900 Basic.
-
OPA 9400
9400
Coherent
Optical parametric amplifier providing excitation and gate beams.
-
R1527P
R1527P
Hamamatsu
Photon-counting photomultiplier tube for detecting the signal.
-
SR400
SR400
Stanford Research Systems
Photon counter for digitizing the signal.
-
Coherent Verdi V18
V18
Coherent
Pumped a mode-locked Ti:sapphire oscillator for the experiment.
-
XCB-LiIO3-type-1 SFM-800/500-1000//308-444 nm
XCB-LiIO3-type-1
Cleveland Crystals, Inc.
Nonlinear crystal for focusing sample fluorescence.
-
STS#37261
37261
CVI Laser Corp.
UV-dispersing prism for filtering residual photons.
-
McPherson
UV-optimized monochromator for detecting the signal.
-
登录查看剩余7件设备及参数对照表
查看全部
