Field Squeezing in a Quantum-Dot Molecule Jaynes-Cummings Model

We investigate the field squeezing in a system composed of an initial coherent field interacting with two quantum dots coupled by electron tunneling. An approximate quantum-dot molecule Jaynes-Cummings model describing the system is given, and the effects of physical quantities, such as the temperature, phonon-electron interaction, mean photon number, field detuning, and tunneling-level detuning, are discussed in detail.

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Antiresonance of electron tunneling through a four-quantum-dot ring with two side-coupled quantum dots

Physics Letters A ◽

10.1016/j.physleta.2008.01.014 ◽

2008 ◽

Vol 372 (17) ◽

pp. 3085-3088 ◽

Cited By ~ 2

Author(s):

Di Zhang ◽

Jia-ning Ma ◽

Hua Li ◽

Shu-fang Fu ◽

Xuan-Zhang Wang

Keyword(s):

Quantum Dots ◽

Quantum Dot ◽

Electron Tunneling ◽

Coupled Quantum Dots

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Electron Interaction in a Quantum Dot with Hard Wall Confinement Potential

International Journal of Modern Physics B ◽

10.1142/s0217979297000538 ◽

1997 ◽

Vol 11 (08) ◽

pp. 1035-1049 ◽

Cited By ~ 2

Author(s):

A. Matulis ◽

J. O. Fjærestad ◽

K. A. Chao

Keyword(s):

Quantum Dot ◽

State Energy ◽

Electron Tunneling ◽

Numerical Procedure ◽

Perturbation Series ◽

Electron Interaction ◽

Confinement Potential ◽

Single Electron Tunneling ◽

Interaction Regime ◽

Charging Energy

We have investigated the electron interaction energy in a circular quantum dot with hard confinement potential, using a renormalized perturbation series (RPS) approach which interpolates between the perturbation solutions in the weak interaction regime and the asymptotic solutions in the strong interaction regime. The RPS is based on the scaling property of the Hamiltonian, and the numerical procedure is not complicated even when the number of electrons in the dot is not very small. The accuracy of the RPS calculation has been tested with two electrons in a dot, where the RPS ground state energy agrees with the exact numerical solution within 1% relative error. We have performed the RPS calculation for three and four electrons in the dot, from which the Coulomb charging energy is derived. The results suggest the potential application of pillar-shaped quantum dots for single-electron tunneling transistors operating at higher temperatures.

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Electron tunneling in the germanium/silicon heterostructure with germanium quantum dots: theory

Himia Fizika ta Tehnologia Poverhni ◽

10.15407/hftp12.04.306 ◽

2021 ◽

Vol 12 (4) ◽

pp. 306-313

Author(s):

S. I. Pokutnyi ◽

◽

N. G. Shkoda ◽

Keyword(s):

Quantum Dots ◽

Quantum Dot ◽

Electron Tunneling ◽

Infrared Range ◽

Silicon Matrix ◽

Electron States ◽

A Chain ◽

A Charge ◽

Germanium Quantum Dots ◽

Germanium Silicon

It is shown that electron tunneling through a potential barrier that separates two quantum dots of germanium leads to the splitting of electron states localized over spherical interfaces (a quantum dot – a silicon matrix). The dependence of the splitting values of the electron levels on the parameters of the nanosystem (the radius a quantum dot germanium, as well as the distance D between the surfaces of the quantum dots) is obtained. It has been shown that the splitting of electron levels in the QD chain of germanium causes the appearance of a zone of localized electron states, which is located in the bandgap of silicon matrix. It has been found that the motion of a charge-transport exciton along a chain of quantum dots of germanium causes an increase in photoconductivity in the nanosystem. It is shown that in the QD chain of germanium a zone of localized electron states arises, which is located in the bandgap of the silicon matrix. Such a zone of local electron states is caused by the splitting of electron levels in the QD chain of germanium. Moreover, the motion of an electron in the zone of localized electron states causes an increase in photoconductivity in the nanosystem. The effect of increasing photoconductivity can make a significant contribution in the process of converting the energy of the optical range in photosynthesizing nanosystems. It has been found that comparison of the splitting dependence of the exciton level Eех(а) at a certain radius a QD with the experimental value of the width of the zone of localized electron states arising in the QD chain of germanium, allows us to obtain the distances D between the QD surfaces. It has been shown that by changing the parameters of Ge/Si heterostructures with germanium QDs (radius of a germanium QD, as well as the distance D between the surfaces of the QDs), it is possible to vary the positions and widths of the zones of localized electronic states. The latter circumstance opens up new possibilities in the use of such nanoheterostructures as new structural materials for the creation of new nano-optoelectronics and nano-photosynthesizing devices of the infrared range.

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NiAg-graphene quantum dot-graphene hybrid with high oxidase-like catalytic activity for sensitive colorimetric detection of malathion

New Journal of Chemistry ◽

10.1039/d1nj00621e ◽

2021 ◽

Author(s):

Xu Dan ◽

Ruiyi Li ◽

Qinsheng Wang ◽

Yongqiang Yang ◽

Haiyan Zhu ◽

...

Keyword(s):

Quantum Dots ◽

Graphene Oxide ◽

Catalytic Activity ◽

Quantum Dot ◽

Colorimetric Detection ◽

Graphene Quantum Dots ◽

Functionalized Graphene ◽

Graphene Quantum Dot ◽

Nickel Silver

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...

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Effect of Growth Temperature on the Characteristics of CsPbI3-Quantum Dots Doped Perovskite Film

Molecules ◽

10.3390/molecules26154439 ◽

2021 ◽

Vol 26 (15) ◽

pp. 4439

Author(s):

Shui-Yang Lien ◽

Yu-Hao Chen ◽

Wen-Ray Chen ◽

Chuan-Hsi Liu ◽

Chien-Jung Huang

Keyword(s):

Thin Films ◽

Thermal Stability ◽

Quantum Dots ◽

Quantum Dot ◽

Growth Temperature ◽

Electron Mobility ◽

Surface Defects ◽

Different Temperatures ◽

Pb Doping ◽

Pristine Film

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.

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Carbon quantum dot-sensitized hollow TiO2 spheres for high-performance visible light photocatalysis

New Journal of Chemistry ◽

10.1039/d1nj00501d ◽

2021 ◽

Author(s):

Xianfeng Zhang ◽

Zongqun Li ◽

Shaowen Xu ◽

Yaowen Ruan

Keyword(s):

Quantum Dots ◽

Quantum Dot ◽

Visible Light ◽

Photocatalytic Degradation ◽

High Performance ◽

Carbon Quantum Dots ◽

Visible Light Photocatalysis ◽

Carbon Quantum Dot ◽

Visible Light Photocatalytic

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.

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Flexible and efficient perovskite quantum dot solar cells via hybrid interfacial architecture

Nature Communications ◽

10.1038/s41467-020-20749-1 ◽

2021 ◽

Vol 12 (1) ◽

Cited By ~ 1

Author(s):

Long Hu ◽

Qian Zhao ◽

Shujuan Huang ◽

Jianghui Zheng ◽

Xinwei Guan ◽

...

Keyword(s):

Thin Film ◽

Quantum Dots ◽

Solar Cells ◽

Quantum Dot ◽

High Performance ◽

Mechanical Stability ◽

Mechanical Adhesion ◽

Perovskite Quantum Dots ◽

Efficient Charge ◽

Photovoltaic Technologies

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.

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