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quantum dot biosensor combined with antibody and aptamer for tracing food-borne pathogens

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Food Quality and Safety 2021年第4期5卷 297-306页

作者： Feifei Sun Jing Zhang Qingli Yang Wei Wu College of Food Science and Engineering Qingdao Agricultural UniversityQingdaoChina

Due to the increasing number of food-borne diseases,more attention is being paid to food ***-borne pathogens are the main cause of food-borne diseases,which seriously endanger human health,so it is necessary to detect and control *** detection methods cannot meet the requirements of rapid detection of food due to many shortcomings,such as being time-consuming,laborious or requiring expensive *** dots have become a promising nanotechnology in pathogens tracking and detection because of their excellent optical *** biosensor detection methods based on quantum dots are have been gradually developed due to their high sensitivity and high *** this review,we summarize the different characteristics of quantum dots synthesized by carbon,heavy metals and composite materials ***,attention is paid to the principles,advantages and limitations of the quantum dots biosensor with antibodies and aptamers as recognition elements for recognition and capture of food-borne ***,the great potential of quantum dots in pathogen detection is summarized.

关键词： quantum dot food-borne pathogen detection synthetic material biosensor

Highly efficient quantum dot light-emitting diodes with the utilization of an organic emission layer

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Nano Research 2023年第7期16卷 10545-10551页

作者： Yang Li Dejiang Zhao Wei Huang Zhiqiang Jiao Lu Wang Qingyu Huang Peng Wang Mengna Sun Guangcai Yuan BOE Technology Group. Ltd.Beijing 100176China

The relative balance of electron and hole injection is crucial for the achievement of highly efficient quantum dot(QD)lightemitting diodes(QLEDs).Here,an inverted red QLED with the utilization of an organic emitting layer(EML)was obtained,exhibiting peak current efficiency(CE)and external quantum efficiency(EQE)of 25.63 cd/A and 23.20%,*** the proposed device,the organic EML,which is a blend of fac-tris(2-phenylpyridine)iridium(Ir(ppy)_(3))and 4,4’-bis(N-carbazolyl)-1,1’-biphenyl(CBP),works as an exciton harvester to capture the leaked electrons from QD layer and the injected holes from hole transporting layer(HTL),then affording energy transfer from organic EML to the adjacent QD layer so that the emission of QD is enhanced *** the same time,according to the results of hole-only and electron-only devices,the insertion of organic EML promotes the hole injection,and eliminates excess electrons from QD to HTL,thus leading to a better match of hole and electron injection in the *** the basis of the above benefits,the optimal QLED with a 10 nm organic EML offered~2-fold improvements of CE and EQE,respectively,relative to the control ***,a better operational lifetime of QLEDs based on the organic EML was achieved.

关键词： quantum dot light emitting diodes organic emitting layer energy transfer

Thermodynamic behaviour of Rashba quantum dot in the presence of magnetic field

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Chinese Physics B 2016年第5期25卷 262-267页

作者： Sukirti Gumber Manoj Kumar Pradip Kumar Jha Man Mohan Department of Physics & Astrophysics University of Delhi Department of Physics DDU College University of Delhi

The thermodynamic properties of an In Sb quantum dot have been investigated in the presence of Rashba spin–orbit interaction and a static magnetic field. The energy spectrum and wave-functions for the system are obtained by solving the Schrodinger wave-equation analytically. These energy levels are employed to calculate the specific heat, entropy,magnetization and susceptibility of the quantum dot system using canonical formalism. It is observed that the system is susceptible to maximum heat absorption at a particular value of magnetic field which depends on the Rashba coupling parameter as well as the temperature. The variation of specific heat shows a Schottky-like anomaly in the low temperature limit and rapidly converges to the value of 2kB with the further increase in temperature. The entropy of the quantum dot is found to be inversely proportional to the magnetic field but has a direct variation with temperature. The substantial effect of Rashba spin–orbit interaction on the magnetic properties of quantum dot is observed at low values of magnetic field and temperature.

关键词： quantum dot Rashba spin–orbit interaction thermal and magnetic properties

Phonon-dependent transport through a serially coupled double quantum dot system

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Chinese Physics B 2014年第5期23卷 510-515页

作者： M.Bagheri Tagani H.Rahimpour Soleimani Department of Physics University of Guilan

Using Keldysh nonequilibrium Green function formalism and mapping a many-body electron-phonon interaction onto a one body problem, the electron transport through a serially coupled double quantum dot system is analyzed. The influence of the electron-phonon interaction, temperature, detuning, and interdot tunneling on the transmission coefficient and current is studied. Our results show that the electron-phonon interaction results in the appearance of the side peaks in the transmission coefficient, whose height is strongly dependent on the phonon temperature. We have also found that the inequality of the electron-phonon interaction strength in two dots gives rise to an asymmetry in the current-voltage characteristic. In addition, the temperature difference between the phonon and electron subsystems results in the reduction of the saturated current and the destruction of the step-like behavior of the current. It is also observed that the detuning can improve the magnitude of the current by compensating the mismatch of the quantum dots energy levels induced by the electron-phonon interaction.

关键词： quantum dot electron-phonon interaction Keldysh nonequilibrium Green function formalism,current-voltage characteristic

Exciton recycling via InP quantum dot funnels for luminescent solar concentrators

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Nano Research 2021年第5期14卷 1488-1494页

作者： Houman Bahmani Jalali Sadra Sadeghi Isinsu Baylam Mertcan Han Cleva W.Ow-Yang Alphan Sennaroglu Sedat Nizamoglu Graduate School of Biomedical Sciences and Engineering KoçUniversityIstanbul34450Turkey Graduate School of Material Science and Engineering KoçUniversityIstanbul34450Turkey KoçUniversity Surface Science and Technology Center(KUYTAM) KoçUniversityIstanbul34450Turkey Laser Research Laboratory KoçUniversityIstanbul34450Turkey Department of Electrical and Electronics Engineering KoçUniversityIstanbul34450Turkey Department of Material Science and Nano Engineering Sabanci UniversityIstanbul34956Turkey

Luminescent solar concentrators (LSC) absorb large-area solar radiation and guide down-converted emission to solar cells for electricity production. quantum dots (QDs) have been widely engineered at device and quantum dot levels for LSCs. Here, we demonstrate cascaded energy transfer and exciton recycling at nanoassembly level for LSCs. The graded structure composed of different sized toxic-heavy-metal-free InP/ZnS core/shell QDs incorporated on copper doped InP QDs, facilitating exciton routing toward narrow band gap QDs at a high nonradiative energy transfer efficiency of 66%. At the final stage of non-radiative energy transfer, the photogenerated holes make ultrafast electronic transitions to copper-induced mid-gap states for radiative recombination in the near-infrared. The exciton recycling facilitates a photoluminescence quantum yield increase of 34% and 61% in comparison with semi-graded and ungraded energy profiles, respectively. Thanks to the suppressed reabsorption and enhanced photoluminescence quantum yield, the graded LSC achieved an optical quantum efficiency of 22.2%. Hence, engineering at nanoassembly level combined with nonradiative energy transfer and exciton funneling offer promise for efficient solar energy harvesting.

关键词： energy transfer indium phosphide quantum dot light harvesting luminescent solar concentrator luminescent solar concentrators(LSC)

Approximate calculation of electronic energy levels of axially symmetric quantum dot and quantum ring by using energy dependent effective mass

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Chinese Physics B 2009年第1期18卷 9-15页

作者：刘玉敏俞重远任晓敏 Institute of Optical Communication and Optoelectronics Beijing University of Posts and Telecommunications Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education(Beijing University of Posts and Telecommunications)

Calculations of electronic structures about the semiconductor quantum dot and the semiconductor quantum ring are presented in this paper. To reduce the calculation costs, for the quantum dot and the quantum ring, their simplified axially symmetric shapes are utilized in our analysis. The energy dependent effective mass is taken into account in solving the Schrodinger equations in the single band effective mass approximation. The calculated results show that the energy dependent effective mass should be considered only for relatively small volume quantum dots or small quantum rings. For large size quantum materials, both the energy dependent effective mass and the parabolic effective mass can give the same results. The energy states and the effective masses of the quantum dot and the quantum ring as a function of geometric parameters are also discussed in detail.

关键词： quantum dot strain quantum ring and electronic structure

Electrical manipulation of a hole‘spin'–orbit qubit in nanowire quantum dot:The nontrivial magnetic field effects

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Chinese Physics B 2023年第3期32卷 125-130页

作者：李睿张航 Key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China

Strong‘spin’–orbit coupled one-dimensional hole gas is achievable in a Ge nanowire in the presence of a strong magnetic *** strong magnetic field lifts the two-fold degeneracy in the hole subband dispersions,so that the effective low-energy subband dispersion exhibits strong spin–orbit ***,we study the electrical spin manipulation in a Ge nanowire quantum dot for both the lowest and second lowest hole subband *** a finite square well to model the quantum dot confining potential,we calculate exactly the level splitting of the spin–orbit qubit and the Rabi frequency in the electric-dipole spin *** spin–orbit coupling modulated longitudinal g-factor gso is not only non-vanishing but also magnetic field ***,the spin–orbit couplings of the lowest and second lowest subband dispersions have opposite magnetic dependences,so that the results for these two subband dispersions are totally *** should be noticed that we focus only on the properties of the hole‘spin’instead of the real hole spin.

关键词： quantum dot hole spin spin–orbit coupling electric-dipole spin resonance

Kondo transport through a quantum dot coupled with side quantum-dot structures

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Chinese Physics B 2010年第7期19卷 1-7页

作者：江兆潭 Department of Physics Beijing Institute of Technology Department of Physics Oklahoma State UniversityStillwaterOklahoma 74078USA

This paper investigates Kondo transport properties in a quadruple quantum dot （QD） based on the slave-boson mean field theory and the non-equilibrium Green＇s function. In the quadruple QD structure one Kondo-type QD sandwiched between two leads is side coupled to two separate QD structures： a single-QD atom and a double-QD molecule. It shows that the conductance valleys and peaks always appear in pairs and by tuning the energy levels in three side QDs, the one-, two-, or three-valley conductance pattern can be obtained. Furthermore, it finds that whether the valley and the peak can appear is closely dependent on the specific values of the interdot couplings and the energy level difference between the two QDs in the molecule. More interestingly, an extra novel conductance peak can be produced by the coexistence of the two different kinds of side QD structures.

关键词： quantum transport Kondo effect quantum dot

Electrically pumped terahertz laser based on a topological insulator quantum dot array

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Science China(Physics,Mechanics & Astronomy) 2021年第1期64卷 82-90页

作者： YongWei Huang LiKun Shi Jun Li WenKai Lou HuiHong Yuan Wen Yang Kai Chang State Key Laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing100083China CAS Center for Excellence in Topological quantum Computation University of Chinese Academy of SciencesBeijing100190China Department of Physics Semiconductor Photonics Research CenterXiamen UniversityXiamen361005China Beijing Academy of quantum Information Sciences Beijing100193China Beijing Computational Science Research Center Beijing100193China

The energy level separation between the edge states in topological insulator quantum dots lies in the terahertz(THz) *** confinement ensures the nonuniformity of the energy level separation near the Dirac point. Based on these features, we propose that a topological insulator quantum dot array can be operated as an electrically pumped continuous-wave THz laser. The proposed device can operate at room temperature, with power exceeding 10 mW and quantum efficiency reaching ~50%. This study may promote the usage of topological insulator quantum dots as an important source of THz radiation.

关键词： terahertz topological insulator quantum dot and quantum confinement effect