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Theory and Properties of Atomic Spacetime
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作者 Sergei Yu. Eremenko 《Journal of Applied Mathematics and Physics》 2024年第6期1967-2006,共40页
Following A. Einsteins aspirations for an atomic theory, a novel theory of spacetime quantization/atomization based on finite Atomic AString Functions evolving since the 1970s is offered. Atomization Theorems allow re... Following A. Einsteins aspirations for an atomic theory, a novel theory of spacetime quantization/atomization based on finite Atomic AString Functions evolving since the 1970s is offered. Atomization Theorems allow representing polynomials, analytic functions, and solutions of General Relativity via the superposition of solitonic atoms which can be associated with flexible spacetime quanta, metriants, or elementary distortions. With multiple interpretations discussed, discrete-continuous spacetime is conceptualized as a lattice network of flexible solitonic atoms adjusting locations to reproduce different metrics. The theory may offer some variants of unified field theory under research based on Atomic AString Function where, like in string theory, fields become interconnected having a common mathematical ancestor. 展开更多
关键词 SPACETIME quantum Atomic Function AString SOLITON Metriant Unified Theory
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A Quantum Chemistry Study on Structural Properties of Petroleum Resin 被引量:1
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作者 Wang Daxi Pan Yueqiu Zhang Hongye 《Petroleum Science》 SCIE CAS CSCD 2007年第4期89-93,共5页
The geometries of resins with single-layer (SG), double-layer (DG) and triple-layer (TG) were calculated with the quantum chemistry method. The geometries and net charges of atoms were obtained. The calculated a... The geometries of resins with single-layer (SG), double-layer (DG) and triple-layer (TG) were calculated with the quantum chemistry method. The geometries and net charges of atoms were obtained. The calculated average distances between layers were 0.5348 nm and 0.5051 nm and the action energies were -9.6355 kJ/mol and -32.2803 kJ/mol for resins DG and TG, respectively. Higher electronegative polar atoms can easily form hydrogen bonds with hydrogen atoms of other resin molecules, resulting in resin aggregates. The minimum cross-sectional diameters of resin molecules are too large to enter the pores of zeolite, so they are likely to crack on the surface of zeolite. 展开更多
关键词 Petroleum resin structure property quantum chemistry catalytic cracking
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Measurement of quantum defects of nS and nD states using field ionization spectroscopy in ultracold cesium atoms 被引量:1
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作者 张临杰 冯志刚 +3 位作者 李安玲 赵建明 李昌勇 贾锁堂 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第5期1838-1842,共5页
This paper reports that ultracold atoms are populated into different nS and nD Rydberg states (n=25-52) by two-photon excitation. The ionization spectrum of an ultracold Rydberg atom is acquired in a cesium magneto-... This paper reports that ultracold atoms are populated into different nS and nD Rydberg states (n=25-52) by two-photon excitation. The ionization spectrum of an ultracold Rydberg atom is acquired in a cesium magneto-optical trap by using the method of pulse field ionization. This denotes nS and nD states in the ionization spectrum and fits the data of energy levels of different Rydberg states to obtain quantum defects of nS and nD states. 展开更多
关键词 ultracold Rydberg atoms quantum defect field ionization spectrum two-photon excitation
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Electronic structure and magnetic properties of substitutional transition-metal atoms in GaN nanotubes 被引量:2
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作者 张敏 史俊杰 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第1期384-389,共6页
The electronic structure and magnetic properties of the transition-metal (TM) atoms (Sc-Zn, Pt and Au) doped zigzag GaN single-walled nanotubes (NTs) are investigated using first-principles spin-polarized densit... The electronic structure and magnetic properties of the transition-metal (TM) atoms (Sc-Zn, Pt and Au) doped zigzag GaN single-walled nanotubes (NTs) are investigated using first-principles spin-polarized density functional calculations. Our results show that the bindings of all TM atoms are stable with the binding energy in the range of 6-16 eV. The Sc- and V-doped GaN NTs exhibit a nonmagnetic behavior. The GaN NTs doped with Ti, Mn, Ni, Cu and Pt are antiferromagnetic. On the contrary, the Cr-, Fe-, Co-, Zn- and Au-doped GaN NTs show the ferromagnetic characteristics. The Mn- and Co- doped GaN NTs induce the largest local moment of 4#B among these TM atoms. The local magnetic moment is dominated by the contribution from the substitutional TM atom and the N atoms bonded with it. 展开更多
关键词 transition-metal atom doping electronic structure magnetic property spin-polarized density-functional calculation
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Entanglement and Quantum Discord of Two Moving Atoms 被引量:1
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作者 Nour Zidan 《Applied Mathematics》 2014年第16期2485-2492,共8页
In this paper we discuss two measures for the quantumness of correlations (quantum discord and entanglement) of two isolated moving atoms which are initially in Werner state. We compare and analyze the effect of the a... In this paper we discuss two measures for the quantumness of correlations (quantum discord and entanglement) of two isolated moving atoms which are initially in Werner state. We compare and analyze the effect of the atomic motion in quantum discord and entanglement. The results show that the atomic motion related to the field mode structure parameter can make the entanglement and quantum discord evolve periodically. The results also indicate that the entanglement suddenly disappears during the evaluation but quantum discord remains non zero, so quantum discord is considered as indicator of disentanglement. 展开更多
关键词 quantum DISCORD CONCURRENCE MOVING atoms Werner State
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Hydrothermal Synthesis,Crystal Structure,Spectrum Properties and Quantum Chemical Calculation of a Trinuclear Copper(Ⅱ) Complex with 3-(Pyridin-2-yl)-1,2,4-triazole 被引量:1
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作者 李昶红 李薇 +1 位作者 李玉林 杨颖群 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第8期1089-1094,共6页
A three-dimensional framework copper(Ⅱ) coordination polymer with copper carbonate basic and 3-(pyridin-2-yl)-1,2,4-triazole (Hpt) has been hydrothemally synthesized.The complex (2,C14 H10 CuN8 ·3H2 O) c... A three-dimensional framework copper(Ⅱ) coordination polymer with copper carbonate basic and 3-(pyridin-2-yl)-1,2,4-triazole (Hpt) has been hydrothemally synthesized.The complex (2,C14 H10 CuN8 ·3H2 O) crystallizes in tetragonal,space group P4 2 /n,a=2.08581(12),b=2.08581(12),c=0.72331(4) nm,M r=761.73,V=3.1468(3) nm 3,Dc=1.608 g/cm 3,Z=4,F(000)=1552,GOOF=1.07,R=0.0515 and wR=0.1689.Every asymmetric unit molecular structure of the complex is composed with one copper ion,one and half water molecules and two Hpt molecules.Each copper ion is coordinated with five nitrogen atoms from four Hpt molecules,forming a distorted square pyramidal geometry.The fluorescence spectrum analysis shows that the title complex at room temperature exhibits intense photoluminescence with maximum emission at 450 nm.The quantum chemistry calculation study on the complex has been performed.The stability,some frontier molecular orbital energies and composition characteristics of some frontier molecular orbitals of the complex have been investigated. 展开更多
关键词 trinuclear copper complex hydrothermal synthesis spectrum properties quantum chemical calculation
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Microwave electrometry with Rydberg atoms in a vapor cell using microwave amplitude modulation
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作者 郝建海 贾凤东 +9 位作者 崔越 王昱寒 周飞 刘修彬 张剑 谢锋 白金海 尤建琦 王宇 钟志萍 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期65-74,共10页
We have theoretically and experimentally studied the dispersive signal of the Rydberg atomic electromagneticallyinduced transparency(EIT)Autler–Townes(AT)splitting spectra obtained using amplitude modulation of the m... We have theoretically and experimentally studied the dispersive signal of the Rydberg atomic electromagneticallyinduced transparency(EIT)Autler–Townes(AT)splitting spectra obtained using amplitude modulation of the microwave(MW)electric field.In addition to the two zero-crossing points interval△f_(zeros),the dispersion signal has two positive maxima with an interval defined as the shoulder interval△f_(sho),which is theoretically expected to be used to measure a much weaker MW electric field.The relationship of the MW field strength E_(MW)and△f_(sho)is experimentally studied at the MW frequencies of 31.6 GHz and 9.2 GHz respectively.The results show that△f_(sho)can be used to characterize the much weaker E_(MW)than that of△f_(zeros)and the traditional EIT–AT splitting interval△f_(m);the minimum E_(MW)measured by△f_(sho)is about 30 times smaller than that by△f_(m).As an example,the minimum E_(MW)at 9.2 GHz that can be characterized by△f_(sho)is 0.056 mV/cm,which is the minimum value characterized by the frequency interval using a vapor cell without adding any auxiliary fields.The proposed method can improve the weak limit and sensitivity of E_(MW)measured by the spectral frequency interval,which is important in the direct measurement of weak E_(MW). 展开更多
关键词 quantum sensor Rydberg atoms electromagnetically induced transparency amplitude modulation
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Scanning transmission electron microscopy and atom probe tomography analysis of non-stoichiometry long-period-stacking-ordered structures in Mg-Ni-Y/Sm alloys
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作者 Yimeng Chen Manuel Legrée +1 位作者 Jean-Louis Bobet Alexander Kvit 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期954-965,共12页
The long-period-stacking-ordered(LPSO)structure affects the mechanical,corrosion and hydrolysis properties of Mg alloys.The current work employs high angle annular dark field-scanning transmission electron microscopy(... The long-period-stacking-ordered(LPSO)structure affects the mechanical,corrosion and hydrolysis properties of Mg alloys.The current work employs high angle annular dark field-scanning transmission electron microscopy(HAADF-STEM)and atom probe tomography(APT)to investigate the structural and local chemical information of LPSO phases formed in Mg-Ni-Y/Sm ternary alloys after extended isothermal annealing.Depending on the alloying elements and their concentrations,Mg-Ni-Y/Sm develops a two-phase LPSO+α-Mg structure in which the LPSO phase contains defects,hybrid LPSO structure,and Mg insertions.HAADF-STEM and APT indicate non-stoichiometric LPSO with incomplete Ni_(6)(Y/Sm)_(8) clusters.In addition,the APT quantitatively determines the local composition of LPSO and confirms the presence of Ni within the Mg bonding layers.These results provide insight into a better understanding of the structure and hydrolysis properties of LPSO-Mg alloys. 展开更多
关键词 Magnesium alloys Long-range ordering Atom probe tomography(APT) STEM HAADF Hydrolysis properties.
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Construction of Laguerre polynomial's photon-added squeezing vacuum state and its quantum properties
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作者 卢道明 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第3期70-74,共5页
Laguerre polynomial's photon-added squeezing vacuum state is constructed by operation of Laguerre polynomial's photon-added operator on squeezing vacuum state. By making use of the technique of integration wit... Laguerre polynomial's photon-added squeezing vacuum state is constructed by operation of Laguerre polynomial's photon-added operator on squeezing vacuum state. By making use of the technique of integration within an ordered product of operators, we derive the normalization coefficient and the calculation expression of (a^1a^+). Its statistical properties, such as squeezing, the anti-bunching effect, the sub-Poissonian distribution property, the negativity of Wigner function, etc., are investigated. The influences of the squeezing parameter on quantum properties are discussed. Numerical results show that,firstly, the squeezing effect of the 1-order Laguerre polynomial's photon-added operator exciting squeezing vacuum state is strengthened, but its anti-bunching effect and sub-Poissonian statistical property are weakened with increasing squeezing parameter;secondly, its squeezing effect is similar to that of squeezing vacuum state, but its anti-bunching effect and subPoissonian distribution property are stronger than that of squeezing vacuum state. These results show that the operation of Laguerre polynomial's photon-added operator on squeezing vacuum state can enhance its non-classical properties. 展开更多
关键词 quantum optics LAGUERRE polynomial's OPERATOR SQUEEZING VACUUM state quantum property
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Quantum Properties of Two-Mode Squeezed Even and Odd Coherent States 被引量:1
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作者 ZHANG Jing WU Wei MENG Shao-Ying 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期317-324,共8页
量状态的二种新类型被使用操作员构造(尉)= exp (尉 ~*ab -尉 a b ) 在二模式的平、奇怪的协调状态上。数学并且量如此的状态的统计性质被调查。这些状态的各种各样的非古典的特征例如挤压性质,内部模式的光子 bunching,和违背 ofCau... 量状态的二种新类型被使用操作员构造(尉)= exp (尉 ~*ab -尉 a b ) 在二模式的平、奇怪的协调状态上。数学并且量如此的状态的统计性质被调查。这些状态的各种各样的非古典的特征例如挤压性质,内部模式的光子 bunching,和违背 ofCauchy—Schwarz 不平等,被讨论。处于这些状态的 Wigner 功能详细被学习。 展开更多
关键词 双模叠加奇数相干态 双模叠加偶数相干态 量子统计性质 保范算子
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STRUCTURES,PROPERTIES AND QUANTUM CHEMISTRY STUDIES OF As-S-X(X=Cl,Br,I)AND As-Y-Br(Y=S,Se,Te)GLASSES
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作者 闵新民 赵修建 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1996年第2期73-77,共5页
As-S-X (X = Cl, Br, I) and As-Y-Br (Y = Sd Se, Te) glasses are studied with Self-Consistent-Field Discrete Variational X(a)(SCF-DV-X(a)) tone of the molecule orbital calculating methods in quantum chemistry. The chemi... As-S-X (X = Cl, Br, I) and As-Y-Br (Y = Sd Se, Te) glasses are studied with Self-Consistent-Field Discrete Variational X(a)(SCF-DV-X(a)) tone of the molecule orbital calculating methods in quantum chemistry. The chemical bonding is studied to discuss the relations between structures and properties with the variations of compositions of the glasses. The calculated results show that the strength of covalent and ionic bonds are both in the order of As-S-Cl > As-S-Br > As-S-I as well as As-S-Br > As-Se-Br > As-Te-Br, it is consistent with the experimental result of the glass-transition temperature (Tg) of the corresponding glasses. The differences of chemical bond strength and Tg among As-S-X (X = Cl ,Br ?I) glasses a-re larger are larger than those among As-Y-Br(Y = S, Se, Te) glasses and the largest difference of chemical bond strength is that of ionic bond of As-X among As-S-X (X = Cl, Br, I) glasses,so the variations of X (X = Cl, Br, I), the end atoms on the chains in the glasses, play the more important role to affect the structure and property of the glasses. 展开更多
关键词 chalcohalide glass structure and property quantum chemistry
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Quantum Chemical Calculation on the Structures and Electronic Properties of Phosphonate Ester as Rare Earth Extractants
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作者 张绍文 沈剑韵 +1 位作者 孙军 王淀佐 《Journal of Rare Earths》 SCIE EI CAS CSCD 1998年第2期2-5,共4页
Molecular mechanics, molecular dynamics and semi empirical quantum chemical method have been used to study the geometric and electronic structures of six phosphonate ester as rare earth extractants. The results show ... Molecular mechanics, molecular dynamics and semi empirical quantum chemical method have been used to study the geometric and electronic structures of six phosphonate ester as rare earth extractants. The results show that the phosphorus atom exhibits sp 3 hybridization. The structures of the extractants are determined by the repulsion of the hydrocarbon groups. In the extractants that have two 2 ethyl hexyl groups, one 2 ethyl hexyl extends straight, and the other extends twistily. When the number of oxygen atom decreases, the negative charge of the phosphoryl oxygen atom increases, but the negative charge of oxygen atom and the positive charge of hydrogen of the hydroxyl group decreases, and the energies of highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital(LUMO) increase. The energies of the occupied frontier orbitals are close to each other. 展开更多
关键词 Rare earths quantum chemical method Rare earth extractant Phosphonate ester Electronic properties Geometric structure
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Quantum Phase Transition of the Bosonic Atoms near the Feshbach Resonance in an Optical Lattice
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作者 李犇 陈景标 《Chinese Physics Letters》 SCIE CAS CSCD 2010年第12期65-68,共4页
The quantum phase transition from the Mott insulator to the superfluid phases of the bosonic atoms trapped in an optical lattice, in which the on-site interaction carl be tuned by a Feshbach resonance, is investigated... The quantum phase transition from the Mott insulator to the superfluid phases of the bosonic atoms trapped in an optical lattice, in which the on-site interaction carl be tuned by a Feshbach resonance, is investigated by a variational approach within mean-field theory. We derive an extended Bos^Hubbard model to describe this ultracold atomic system. By theoretical calculation and analysis, the phase diagram is shown clearly, and we find an exciting and novel phenomenon that is the appearance of the Mort insulator-sea (MI-sea). Meanwhile, the experimental feasibility of observing the MI-sea is discussed by analyzing the published data related to the Fashbaeh resonance at present. Finally, the potential application of the MI-sea for quantum information processing and quantum computation is also discussed in detail 展开更多
关键词 Atomic and molecular physics quantum gases liquids and solids Computational physics Statistical physics and nonlinear systems
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Influence of InAs deposition thickness on the structural and optical properties of InAs quantum wires
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作者 Yuanli Wang Hua Cui +4 位作者 Wen Lei Yahong Su Yonghai Chen Ju Wu Zhanguo Wang 《Journal of University of Science and Technology Beijing》 CSCD 2007年第4期341-344,共4页
The influence of InAs deposition thickness on the structural and optical properties of InAs/InA1As quantum wires (QWR) superlattices (SLS) was studied. The transmission electron microscopy (TEM) results show tha... The influence of InAs deposition thickness on the structural and optical properties of InAs/InA1As quantum wires (QWR) superlattices (SLS) was studied. The transmission electron microscopy (TEM) results show that with increasing the InAs deposited thickness, the size uniformity and spatial ordering of InAs QWR SLS was greatly improved, but threading dislocations initiated from InAs nanowires for the sample with 6 monolayers (MLs) InAs deposition. In addition, the zig-zag features along the extending direc- tion and lateral interlink of InAs nanowires were also observed. The InAs nanowires, especially for the first period, were laterally compact. These structural features may result in easy tunneling and coupling of charge carders between InAs nanowires and will hamper their device applications to some extent. Some suggestions are put forward for further improving the uniformity of the stacked InAs QWRs, and for suppressing the formation of the threading dislocations in InAs QWR SLS. 展开更多
关键词 quantum wire molecular beam epitaxy optical properties NANOSTRUCTURES transmission electron microscope
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Spin transport properties of a Dresselhaus-polygonal quantum ring
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作者 唐翰昭 翟利学 +1 位作者 沈曼 刘建军 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第3期55-60,共6页
We propose a theoretical method to investigate the effect of the Dresselhaus spin–orbit coupling(DSOC) on the spin transport properties of a regular polygonal quantum ring with an arbitrary number of segments. We f... We propose a theoretical method to investigate the effect of the Dresselhaus spin–orbit coupling(DSOC) on the spin transport properties of a regular polygonal quantum ring with an arbitrary number of segments. We find that the DSOC can break the time reversal symmetry of the spin conductance in a polygonal ring and that this property can be used to reverse the spin direction of electrons in the polygon with the result that a pure spin up or pure spin down conductance can be obtained by exchanging the source and the drain. When the DSOC is considered in a polygonal ring with Rashba spin–orbit coupling(RSOC) with symmetric attachment of the leads, the total conductance is independent of the number of segments when both of the two types of spin–orbit coupling(SOC) have the same value. However, the interaction of the two types of SOC results in an anisotropic and shape-dependent conductance in a polygonal ring with asymmetric attachment of the leads. The method we proposed to solve for the spin conductance of a polygon can be generalized to the circular model. 展开更多
关键词 Dresselhaus spin–orbit coupling spin transport property polygonal quantum ring
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Some studies of the interaction between two two-level atoms and SU(1,1) quantum systems
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作者 T M El-Shahat M Kh Ismail 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第10期116-122,共7页
Herein, we present an approach to look for the best phenomenon to measure quantum correlation. The system of two isolated qubits each interacting with a single-mode cavity was theoretically created to study the quantu... Herein, we present an approach to look for the best phenomenon to measure quantum correlation. The system of two isolated qubits each interacting with a single-mode cavity was theoretically created to study the quantum correlation. Some of the phenomena, such as the quantum discord and concurrence, were generated through such a system. The influences of initial state purity, qubit motion, and detuning parameters were discussed for the phenomena. These parameters for a specific value show that the behavior of phenomena are analogous. It is interesting to mention that some values of detuning undergo a sudden death of phenomena, and the quantum discord still captures the qubits quantum correlation. We predict that the quantum discord may be a better measure of quantum correlation than concurrence. 展开更多
关键词 an isolated atom with a cavity SU (1 1) quantum discord concurrence
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Fabrication and optical properties of InGaN/GaN multiple quantum well light emitting diodes with amorphous BaTiO_3 ferroelectric film
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作者 彭静 吴传菊 +6 位作者 孙堂友 赵文宁 吴小锋 刘文 王双保 揭泉林 徐智谋 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第6期504-509,共6页
BaTiO3 (BTO) ferroelectric thin films are prepared by the sol,el method. The fabrication and the optical properties of an InGaN/GaN multiple quantum well light emitting diode (LED) with amorphous BTO ferroelectric... BaTiO3 (BTO) ferroelectric thin films are prepared by the sol,el method. The fabrication and the optical properties of an InGaN/GaN multiple quantum well light emitting diode (LED) with amorphous BTO ferroelectric thin film are studied. The photolumineseence (PL) of the BTO ferroelectric film is attributed to the structure. The ferroeleetric film which annealed at 673 K for 8 h has the better PL property. The peak width is about 30 nm from 580 nm to 610 nm, towards the yellow region. The mixed electroluminescence (EL) spectrum of InGaN/GaN multiple quantum well LED with 150-nm thick amorphous BTO ferroelectric thin film displays the blue-white light. The Commission Internationale De L'Eclairage (CIE) coordinate of EL is (0.2139, 0.1627). EL wavelength and intensity depends on the composition, microstructure and thickness of the ferroelectric thin film. The transmittance of amorphous BTO thin film is about 93% at a wavelength of 450 nm-470 nm. This means the amorphous ferroelectrie thin films can output more blue-ray and emission lights. In addition, the amorphous ferroelectric thin films can be directly fabricated without a binder and used at higher temperatures (200 ℃-400 ℃). It is very favourable to simplify the preparation process and reduce the heat dissipation requirements of an LED. This provides a new way to study LEDs. 展开更多
关键词 InGaN/GaN multiple quantum well light emitting diodes ferroelectric film BaTiO3 optical properties
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Analysis of Nonequilibrium Transport Properties of Interacting Quantum Wire Models
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作者 Yangdong Zheng 《Journal of Applied Mathematics and Physics》 2019年第8期1677-1685,共9页
We analyze nonequilibrium electronic transport properties of a typical interacting three-site quantum wire model within Hartree-Fock approximation making use of Keldysh formalism. Some rigorous formulas are provided f... We analyze nonequilibrium electronic transport properties of a typical interacting three-site quantum wire model within Hartree-Fock approximation making use of Keldysh formalism. Some rigorous formulas are provided for direct calculations when Coulomb repulsion is present. According to numerical calculations using above formulas, we investigate the conductance, transport currents, and on site electronic charges of the wire on some special occasions in the interacting case, and also compare them with the results in the noninteracting case. 展开更多
关键词 quantum Wire Model NONEQUILIBRIUM TRANSPORT PROPERTY CONDUCTANCE Keldysh FORMALISM
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Effects of Growth Conditions on Optical Properties ofGa In NAs/Ga As Quantum Well Grown by Molecular Beam Epitaxy
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作者 李联合 潘钟 +3 位作者 张伟 林耀望 王学宇 吴荣汉 《Journal of Semiconductors》 CSCD 北大核心 2000年第12期1152-1156,共5页
During the process of molecular beam epitaxy employing a DC plasma as N source, the effects of the growth temperature, growth rate and As 4 pressure on the optical properties of GaInNAs Quantum Well(QW) are similar to... During the process of molecular beam epitaxy employing a DC plasma as N source, the effects of the growth temperature, growth rate and As 4 pressure on the optical properties of GaInNAs Quantum Well(QW) are similar to those of InGaAs QW with the same In contents. In the range of 400 to 470℃, elevating growth temperature is beneficial to the improvement in the photoluminescence (PL) peak intensity of GaInNAs QW, but obviously broadens the full width at half maximum PL peak. The improvement of optical properties and the reduction of N incorporation have been observed by increasing the growth rate. As 4 pressure mainly affects the optical properties of GaInNAs QW rather than N incorporation does. 展开更多
关键词 optical properties quantum well MBE
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Preparation and Optical Properties Assessment of CdSe Quantum Dots
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作者 Gholam Reza Amiri Soheil Fatahian Somayeh Mahmoudi 《Materials Sciences and Applications》 2013年第2期134-137,共4页
CdSe quantum dots (QDs) (2 - 3 nm) were synthesized by chemical precipitation method. Optical and structure properties of the products were investigated by scanning tunneling microscope (STM), X-ray diffraction (XRD),... CdSe quantum dots (QDs) (2 - 3 nm) were synthesized by chemical precipitation method. Optical and structure properties of the products were investigated by scanning tunneling microscope (STM), X-ray diffraction (XRD), and ultra violet-visible (UV-Vis) spectrophotometer. The results show that high-quality cubic CdSe QDs were obtained. It is also obtained that temperature is one of the most important factors the affect on the particle size and optical properties of the prepared QDs samples. 展开更多
关键词 CDSE quantum DOTS Optical PROPERTY
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