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Electronic and Optical Properties of Hydrogenated Si Clusters

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Chinese Journal of Structural Chemistry 2009年第9期28卷 1093-1098页

作者：刘光华邓小燕王秀清 School of physics Peking University Department of physics Hebei North University

The geometric, electronic, and photoabsorption properties of some hydrogenated silicon clusters are investigated. The density functional theory with generalized gradient approximation fimctional is applied. Our study shows that the geometric structures of them relax with their increasing sizes. Synchronously, the polarizations of Si-H bonds become weak slowly but overlap populations increase. In Mulliken population analysis, we find a distinctive passivation effect （some electrons are transferred from outer Si atoms to the central Si with four-coordinate Si atoms）. Owing to the quantum confinement, the energy gap and the lowest excitation energy increase with the decreasing sizes. For nanometer scale cluster, the transition from the highest occupied molecular orbital to the lowest unoccupied molecular orbital state is usually prohibited.

关键词： hydrogenated Si cluster density functional theory passivation effect

Effect of microstructure on the thermoelectric properties of CSD-grown Bi_2Sr_2Co_2O_y thin films

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Chinese physics B 2013年第3期22卷 453-456页

作者：王淑芳闫国英陈珊珊白子龙王江龙于威傅广生 College of physics Science and Technology Hebei University School of Information Engineering Hebei University of Technology

Three Bi2Sr2Co2Oy thin films with different microstructures have been prepared by chemical solution deposition on LaAlO 3（001） through varying the annealing *** the decrease in the annealing temperature,both the size and c-axis alignment degree of grains in the film decrease as well,leading to an increase in the film *** addition,the decrease in the annealing temperature also results in a slight increase in the Seebeck coefficient due to the enhanced energy filtering effect of the small-grain *** nanostructured Bi2Sr2Co2Oy film with an average grain size of about 100 nm shows a power factor comparable to that of films with larger *** the thermal conductivity of the nanostructured films can be depressed due to the enhanced phonon scattering by grain boundary,a higher figure of merit is expected in Bi2Sr2Co2Oy thin film with grains in nanometer size.

关键词： thermoelectric properties Bi2Sr2Co2Oy thin films microstructure chemical solution deposition

Statistical Parameters for Hydrogen Bonding Networks: One Component Case

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Chinese physics Letters 2001年第6期18卷 764-766页

作者： WANG Hai-Jun HONG Xiao-Zhong ZHAO Min BA Xin-Wu Department of Chemistry Hebei UniversityBaoding 071002 Department of physics Hebei UniversityBaoding 071002

Based on the analysis of network structures formed by hydrogen bonds as the sol-gel phase transition takes place in a single component hydrogen bonding system,the theory of reversible gelation is applied to calculate some statistical parameters that determine many physical and chemical properties of the *** the numerical simulation of the number of active chains and dangling chains,the number of effective cross-linkages,the number of active and dangling mers and the modulus as a function of conversion are undertaken.

关键词： chains modulus bonding

Formation of combined solitons in two-component Bose—Einstein condensates

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Chinese physics B 2010年第8期19卷 139-143页

作者：李秋艳李再东姚淑芳李禄傅广生 Department of Applied physics Hebei University of Technology School of Information Engineering Hebei University of Technology College of physics and Electronics Engineering Shanxi University

We investigate the combined soliton solutions of two-component Bose-Einstein condensates with external potential. The ＂phase diagram＂ is obtained for the formation regions of different combined solitons. Our results show that the intraspecies （interspecies） interaction strengths and the external trapped potential clearly affect the formation of dark- dark, bright-bright, and dark bright soliton solutions in different regions. Especially, we find that the bright bright （dark^dark） soliton can exist in the case of both repulsive （attractive） intraspecies interaction strengths in the presence of external potential. This novel phenomenon is completely different from the formation of soliton solution of one- component Bose-Einstein condensates without external potential, and it will be useful for the study of two-component Bose-Einstein condensates.

关键词： Bose-Einstein condensates combined solitons

Symmetry and size effects on energy and entanglement of an exciton in coupled quantum dots

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Chinese physics B 2013年第4期22卷 389-393页

作者：沈曼白彦魁安兴涛刘建军 College of physics Science & Information Engineering and hebei Advanced Thin Film Laboratory Hebei Normal University School of Sciences Hebei University of Science and Technology physics Department Shijiazhuang University

We study theoretically the essential properties of an exciton in vertically coupled Gaussian quantum dots in the presence of an external magnetic field. The ground state energy of a heavy-hole exciton is split into four energy levels due to the Zeeman effect. For the symmetrical system, the entanglement entropy of the exciton state can reach a value of 1. However, for a system with broken symmetry, it is close to zero. Our results are in good agreement with previous studies.

关键词： exciton coupled Gaussian quantum dot symmetry entanglement entropy

Hadron formation in semi-inclusive deep inelastic lepton-nucleus scattering

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Chinese physics C 2013年第10期37卷 26-32页

作者：宋丽华刘娜段春贵 Department of physics Hebei Normal University College of Science Hebei United University College of Mathematics and physics Shijiazhuang University of Economics hebei Advanced Thin Films Laboratory

Hadron production in lepton-nucleus deep inelastic scattering is studied in a model including quark energy loss and nuclear absorption. The leading-order computations for hadron multiplicity ratios are presented and compared with the selected HERMES experimental data with the quark hadronization occurring inside the nucleus by means of the hadron formation time. It is shown that with increase of the energy fraction carried by the hadron, the nuclear suppression on hadron multiplicity ratio from nuclear absorption gets bigger. It is found that when hadronization occurs inside the nucleus, the nuclear absorption is the dominant mechanism causing a reduction of the hadron yield. The atomic mass dependence of hadron attenuation for quark hadronization starting inside the nucleus is confirmed theoretically and experimentally to be proportional to A1/3.

关键词： deep inelastic scattering nuclei nuclear absorption hadron production

Coherence destruction of tunneling in a quantum-dot molecule with bias

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Chinese physics B 2010年第10期19卷 445-451页

作者：钟光辉王立民 Department of physics Hebei Normal University Institute of Applied physics and Computational Mathematics

This paper studies the constraint conditions for coherence destruction in tunneling by using perturbation theory and numerical simulation for an AC-field with bias and Coulomb interaction between electrons in a quantum dot molecule. Such conditions can be described by using the roots of a Bessel function Jn（x）, where n is determined by both the bias and the Coulomb interactions, and x is the ratio of the amplitude to the frequency of the AC-field. Under such conditions, a coherent suppression of tunneling occurs between localized electronic states, which results from the dynamical localization phenomenon. All the conditions are verified with numerical simulations.

关键词： dynamic localization Floquet state constraint conditions

Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile

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原子与分子物理学报 2025年第4期42卷 27-32页

作者： XU Jian-Qiang MA Zhao-Peng CHENG Si LIU Zhi-Cong ZHU Guang-Lai Department of physics School of Physics and Electronic InformationAnhui Normal UniversityWuhu 241002China

The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this *** following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution *** results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient ***,the excess molar volume initially decreases,reaches a minimum,and then *** rules of radial distribution functions(RDFs)of characteristic atoms are *** increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then *** indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently.

关键词： Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions

Defects‑Rich Heterostructures Trigger Strong Polarization Coupling in Sulfides/Carbon Composites with Robust Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 528-547页

作者： Jiaolong Liu Siyu Zhang Dan Qu Xuejiao Zhou Moxuan Yin Chenxuan Wang Xuelin Zhang Sichen Li Peijun Zhang Yuqi Zhou Kai Tao Mengyang Li Bing Wei Hongjing Wu Mengyang Li Bing Wei Hongjing Wu School of physics Xidian UniversityXi’an 710071People’s Republic of China School of Advanced Materials and Nanotechnology State Key Discipline Laboratory of Wide Band Gap Semiconductor TechnologyXidian UniversityXi’an 710071People’s Republic of China School of Microelectronics Xidian UniversityXi’an 710071People’s Republic of China School of Telecommunication Engineering Xidian UniversityXi’an 710071People’s Republic of China MOE Key Laboratory of Material physics and Chemistry Under Extraordinary School of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China The Ministry of Education Key Laboratory of Micro and Nano Systems forAerospace School of Mechanical EngineeringNorthwestern PolytechnicalUniversityXi’an 710072People’s Republic of China

Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies,as well as veiled dielectric-responsive character,are instrumental in electromagnetic *** methods,however,constrain their delicate ***,an innovative alternative is proposed:carrageenan-assistant cations-regulated(CACR)strategy,which induces a series of sulfides nanoparticles rooted in situ on the surface of carbon *** unique configuration originates from strategic vacancy formation energy of sulfides and strong sulfides-carbon support interaction,benefiting the delicate construction of defects-rich heterostructures in M_(x)S_(y)/carbon composites(M-CAs).Impressively,these generated sulfur vacancies are firstly found to strengthen electron accumulation/consumption ability at heterointerfaces and,simultaneously,induct local asymmetry of electronic structure to evoke large dipole moment,ultimately leading to polarization coupling,i.e.,defect-type interfacial ***“Janus effect”(Janus effect means versatility,as in the Greek two-headed Janus)of interfacial sulfur vacancies is intuitively confirmed by both theoretical and experimental investigations for the first ***,the sulfur vacancies-rich heterostructured Co/Ni-CAs displays broad absorption bandwidth of 6.76 GHz at only 1.8 mm,compared to sulfur vacancies-free CAs without any dielectric *** defects-rich heterostructures,this one-pot CACR strategy may steer the design and development of advanced nanomaterials,boosting functionality across diverse application domains beyond electromagnetic response.

关键词： Defects-rich heterointerfaces Sulfides Polarization coupling Electromagnetic wave absorption