Evolution of the Shape and Size of Ingaas Selforganized Quantum Dots

1999 ◽  
Vol 583 ◽  
Author(s):  
Qianghua Xie ◽  
J. L. Brown ◽  
R. L. Jones ◽  
J. E. Van Nostrand

AbstractWe have found a shape transformation of InGaAs quantum dots formed via a fractional monolayer deposition technique on GaAs (001) surfaces. This is evidenced by the bimodal quantum dot height (peaked at 8.5 nm and 14.5 nm) and aspect ratio (peaked at 0.18 and 0.26) distributions. The lateral size, height, and aspect ratio all become convergent, suggesting a simultaneous quantum dot size equalization and shape stabilization. Photoluminescence peaks red shift as a consequence of dot growth, and their line-widths become smaller due to dot shape stabilization and size equalization. A record low inhomogeneous broadening of 18.4 meV at a wavelength of 1180 nm (4 K) is obtained for vertically-aligned, shape-stabilized, and size-equalized InGaAs dots.

2010 ◽  
Vol 19 (04) ◽  
pp. 595-601 ◽  
Author(s):  
PETTER HOLMSTRÖM ◽  
LARS THYLÉN ◽  
ALEXANDER BRATKOVSKY

Dispersion properties of nanoarray waveguides composed of near-field-coupled arrays of metal-clad quantum dots (QDs) are calculated. The high loss due to operation of the metal shells close to resonance is mitigated by using optical gain in the QDs. The conditions for achieving loss compensated operation are given, with realistic material parameters and neglecting inhomogeneous broadening.


2003 ◽  
Vol 93 (2) ◽  
pp. 1190-1194 ◽  
Author(s):  
Tao Yang ◽  
Shigeru Kohmoto ◽  
Hitoshi Nakamura ◽  
Kiyoshi Asakawa

MRS Advances ◽  
2018 ◽  
Vol 3 (41) ◽  
pp. 2429-2433
Author(s):  
Brian Billstrand ◽  
Kaifu Bian ◽  
Casey Karler ◽  
Hongyou Fan

ABSTRACTA new quantum dot synthesis method based on metallic-block copolymer precursors was developed. The synthesis produced CdS QDs assembled into chains. This method provides a new model for the study of 1D QD chains to determine its effect on charge transport and optoelectronic coupling. This synthesis method was readily extended to other semiconductor materials including PbS and perovskites producing QDs of various shapes. It evidenced further promise of this synthesis method to assist in the assembly, shape and size control of various nanomaterials


2021 ◽  
Author(s):  
Xu Dan ◽  
Ruiyi Li ◽  
Qinsheng Wang ◽  
Yongqiang Yang ◽  
Haiyan Zhu ◽  
...  

The paper reports the synthesis of nickel-silver-graphene quantum dot-graphene hybrid. Histidine-functionalized graphene quantum dots (His-GQDs) were bonded to graphene oxide (GO) and then combined with Ni2+ and Ag+ to form...


Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4439
Author(s):  
Shui-Yang Lien ◽  
Yu-Hao Chen ◽  
Wen-Ray Chen ◽  
Chuan-Hsi Liu ◽  
Chien-Jung Huang

In this study, adding CsPbI3 quantum dots to organic perovskite methylamine lead triiodide (CH3NH3PbI3) to form a doped perovskite film filmed by different temperatures was found to effectively reduce the formation of unsaturated metal Pb. Doping a small amount of CsPbI3 quantum dots could enhance thermal stability and improve surface defects. The electron mobility of the doped film was 2.5 times higher than the pristine film. This was a major breakthrough for inorganic quantum dot doped organic perovskite thin films.


2021 ◽  
Author(s):  
Xianfeng Zhang ◽  
Zongqun Li ◽  
Shaowen Xu ◽  
Yaowen Ruan

TiO2/CQD composites were synthesized through carbon quantum dots covalently attached to the surface of hollow TiO2 spheres for visible light photocatalytic degradation of organics.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Long Hu ◽  
Qian Zhao ◽  
Shujuan Huang ◽  
Jianghui Zheng ◽  
Xinwei Guan ◽  
...  

AbstractAll-inorganic CsPbI3 perovskite quantum dots have received substantial research interest for photovoltaic applications because of higher efficiency compared to solar cells using other quantum dots materials and the various exciting properties that perovskites have to offer. These quantum dot devices also exhibit good mechanical stability amongst various thin-film photovoltaic technologies. We demonstrate higher mechanical endurance of quantum dot films compared to bulk thin film and highlight the importance of further research on high-performance and flexible optoelectronic devices using nanoscale grains as an advantage. Specifically, we develop a hybrid interfacial architecture consisting of CsPbI3 quantum dot/PCBM heterojunction, enabling an energy cascade for efficient charge transfer and mechanical adhesion. The champion CsPbI3 quantum dot solar cell has an efficiency of 15.1% (stabilized power output of 14.61%), which is among the highest report to date. Building on this strategy, we further demonstrate a highest efficiency of 12.3% in flexible quantum dot photovoltaics.


2021 ◽  
Vol 52 (1) ◽  
pp. 953-956
Author(s):  
Tatsuya Ryowa ◽  
Yusuke Sakakibara ◽  
Tadashi Kobashi ◽  
Keisuke Kitano ◽  
Masaya Ueda ◽  
...  

2008 ◽  
Vol 20 (14) ◽  
pp. 1240-1242 ◽  
Author(s):  
Chi-Che Tseng ◽  
Shu-Ting Chou ◽  
Yi-Hao Chen ◽  
Cheng-Nan Chen ◽  
Wei-Hsun Lin ◽  
...  

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