bluuebunny/crossref_metadata_2025 huggingface dataset:
THE GENERALIZED TORTOISE COORDINATE-TRANSFORMATION AND HAWKING PROCESSES
Authors: LI ZHONG-HENG  , ZHAO ZHENG  ,   (1)北京师范大学物理系; (2)湛江师范学院物理系
Published: November 2020

By discussing on the dynamical equations of sorts of particles in the non-stationary Rindler and the Vaidya space-time,it is shown that after introducing new coordinates into a time-dependent metric,the method to define the tortoise coordinate transformation in a stationary space-time can be generalized to a non-stationary case.The character of the obtained tortoise transformation is that the temperature function is obviously dependent on time.It is also shown that the Hawking processes are independent of the source terms in the dynamical equations.Particularly,we find a picture where particle-scattering must be twice in the Hawking radiation described by the general time t such as in the non-stationary Rindler case.
QUANTUM EFFECTS OF CHARGE IN-THE MESOSCOPIC CIRCUIT
Authors: CHEN BIN  , LI YOU-QUAN  , SHA JIAN  , ZHANG QI-RUI  ,   (1)浙江大学物理系; (2)浙江大学物理系;杭州师范学院物理系
Published: November 2020

Based on the fact that the charge is quantized in the mesoscopic circuit,the quantum theory of mesoscopic circuit has been given and the quantum fluctuation in the mesoscopic circuit has also been shown.
ON THE LINEAR SHIFT INVARIANCE OF THE THERMAL WAVE IMAGING
Authors: ZENG SHAO-QUN  , XU HAI-FENG  , LI JIAO-YANG  , LIU XIAO-DE  ,   华中理工大学光电子工程系
Published: November 2020

In the approximation of pertubation,the thermal wave imaging was proved to be linear shift invariant under some conditions.Based on this fact ,the signal formation mechanism of such a system was interpreted when used in nondestructive evaluation of opaque materials.
CRITICAL CHARACTERISTICS OF THE FRACTAL DIFFUSE-FRINGE Au-FILM SYSTEM
Authors: GE HONG-LIANG  , FEN CHUN-MU  , YE GAO-XIANG  , ZHANG QI-RUI  ,   浙江大学物理系
Published: November 2020

The fringe effect on the third-harmonic coefficient and critical current of the fractal diffuse-fringe Au-film system, deposited on fractal substrates, is studied. We show that both the critical current and the film resistivity as exhibit functions of the third-harmonic coefficient exponential critical behavior. However, the critical exponents in the fractal diffuse-fringe Au-film are obviously different from those of other film systems. A discussion of the universality problem is also presented.
SIMULATION OF RAYLEIGH-TAYLOR INSTABILITY BY THE LATTICE BOLTZMANN MODEL
Authors: NIE XIAO-BO  , ZHANG ZHONG-ZHEN  , FU HONG-YUAN  , SHEN LONG-JUN  , WANG JI-HAI  ,   北京应用物理与计算数学研究所
Published: November 2020

We have developed a lattice-Boltzmann model from previous models for multiphase fluid flows to simulate Rayleigh-Taylor instability.A force has been introduced and a 9-velocity square lattice is used.The conservation equation of total mass and momentum can be derived using Chapman-Enskog multiscale expansions.Using this model we have obtained the linear growth and nonlinear growth of bubbles and the mushrooms produced by Rayleigh-Taylor instability.
STUDIES ON MICROSTRUCTURE AND PHOTOLUMINESCENCE PROPERTY OF POROUS SILICON
Authors: LIU XIAO-BING  , SUN JIE-LIN  , YUAN SHUAI  , LIAO LIANG-SHENG  , HE JUN  , MIAO XI-YUE  , FAN HONG-LEI  , XU LEI  , LI MIN-QIAN  , HOU XIAO-YUAN  ,   (1)长沙电力学院物理系; (2)复旦大学应用表面物理国家重点实验室和李政道物理学综合实验室; (3)中国科学院上海原子核研究所核分析中心
Published: November 2020

AFM and PL are adopted to study the morphological and photoluminescent characteristics of a series of porous silicon (PS) samples etched with direct current and pulsed current.The results of AFM indicate that there are many “hillocks” at the surface of PS samples and the microstructure of PS samples is quite different with different etching modes.The amount of the small Si particles formed by pulsed etching is more than that by direct current etching under the-equivalent etching-conditions and the particles appear more protruding and sharper by the pulsed etching.Moreover,PL spectra shows that it is easier to get photoluminescent PS samples with higher intensity by using pulsed etching method.The microstructure of PS samples plays a very important role in the generation of photoluminescence of porous silicon.
SYMMETRIC BEAM FANNING IN PHOTOREFRACTIVE CRYSTALS WITH A LOCAL NONLINEAR RESPONSE
Authors: GUO RU  , LIU SI-MIN  , LING ZHEN-FANG  , XU JING-JUN  , ZHANG GUANG-YIN  ,   南开大学物理系
Published: November 2020

Photorefractive beam fanning was observed in almost all photorefractive crystals with a nonlocal nonlinearity. Recently we observed experimentally symmetrical beam fanning in photorefractive crystal (LiNbO3:Fe) with a local nonlinear response.Based on forward degenerate three-wave interaction,we presented a theoretical study of the symmetrical beam fanning.
INTERACTION OF TWO-MODE SU（1，1） COHERENT STATES WITH THE V-TYPE THREE-LEVEL ATOM IN A KERR-LIKE-MEDIUM
Authors: LAI YUN-ZHONG  , LIANG JIU-QING  ,   (1)山西大学理论物理研究所; (2)太原重型机械学院基础部
Published: November 2020

We first derive the state vector of a V-type three-level atom interacting with two-mode SU (1,1) coherent states in a Kerr-like medium. It is shown by numericl calculations that the Kerr effect results indifferent characters of the Rabi oscillation, as compared with the two-levelatom case, while the correlation of the two-mode coherent states is less affected by the the Kerr medium. We also discuss the influence of Kerr effect on the Cauchy-Schwartz inequality.
HARMONICS IN NOVEL WIGGLER FREE-ELECTRON LASER
Authors: WEN SHUANG-CHUN  ,   衡阳师范高等专科学校物理系
Published: November 2020

A single-particle approach is used to derive the small signal gain for harmonics in the novel wiggler proposed by Pinhas.The results are similar to that in ordinary planar undulator free-electron lasers.
THE GENERATION OF TUNABLE VUV COHERENT RADIATION BY FOUR-WAVE SUM-MIXING BELOW THE FIRST RESONANCE LEVEL OF Ne
Authors: WANG PENG-QIAN  , TIAN CE-CHAN  , SUN TAO-HENG  ,   北京大学物理系
Published: November 2020

Using the output of one dye laser as the fundamental wave,we have generated tunable VUV coherent radiation from 116.6nm through 119.2nm by nonresonant four-wave sum-mixing process below the first resonance level of Ne.The conversion efficiency was found to be comparatively high because of the very small dispersion in this range.We found that the four-wave sum-mixing output was proportional to the square of the gas density we offered.If we increase the gas density of Ne,the conversion efficiency is estimated to be improved by two orders.
THE ACCURATE CALCULATION AND ANALYSIS OF THE PROPAGATOR IN REAL SPACE DYNAMICAL ELECTRON DIFFRACTION CALCULATIONS
Authors: DU KUI  , WANG YUAN-MING  , WANG ZHONG-MING  , ZHU SHI-XUE  ,   中国科学院金属研究所固体原子像开放研究实验室
Published: November 2020

This paper is a systematic study of the real space dynamical electron diffraction involved in propagation calculation and sets down guidelines based on theoretical analysis for consistent and accurate computation for real space dynamical electron diffraction.
POSITRON LIFETIME AND DOPPLER BROADENING TECHNIQUES STUDIES ON THE INTERACTION BETWEEN HYDROGEN AND DEFECTS IN NICKEL
Authors: WU YI-CHU  , ZHU ZHI-YING  , YOSHIKO ITOH  , YASUO ITO  ,   (1)日本东京大学核科学与技术研究中心; (2)日本理化学研究所; (3)中山大学物理系
Published: November 2020

The interaction between hydrogen and defects in annealed,473K tempered and cold-rolled nickel samples has been investigated by positron lifetime and Doppler broadening measurements.Experimental results show that there has been no effect of hydrogen-charging on the nickel samples containing only dislocations,while in the samples containing vacancies the effect was evident.A long-lifetime component appeared for the latter,which may indicate that the hydrogen-vacancy composite is also the center of vacancy agglomeration.
INFLUENCE OF HEAT TREATMENT PROCESS ON MAGNETIC ORDER IN CrCr75(Fe0.67Mn0.33)25 ALLOYS
Authors: XU WEI-MING  ,   中国科学院低温技术实验中心
Published: November 2020

The magnetic order in Cr75(Fe0.67Mn0.33)25 alloy prepared under different annealing conditions is studied by means of 57Fe Mssbauer spectroscopy and bulk magnetization measurements.We get the conclusion that the short-range chemical order plays a dominant role in the magnetic order of the alloy.The heat treatment process affects the Cr(Mn)-rich,Fe-rich clusters in the alloy,thus increases both the ferromagnetic and antiferromagnetic transition temperature greatly.The Cr(Mn),Fe clusters lead to the magnetic phase segregation in the alloy.
THE ORIENTED GROWTH OF C60 FILMS-ON GaAs(100) SUBSTRATE
Authors: YAO JIANG-HONG  , ZOU YUN-JUAN  , ZHANG XING-WANG  , CHEN GUANG-HUA  ,   (1)北京工业大学应用物理系; (2)兰州大学物理系
Published: November 2020

Entirely (111) oriented C60 single films are grown successfully on GaAs (100) substrate by a physical vapor deposition technique with double temperature zone.The structure and morphology of films are studied by X-ray diffraction and SEM.The results show that the highly oriented growth of C60 films occurs only at narrow range of substrate temperature,higher or lower substrate temperature leads to random orientation of grains.A reasonable explanation for experimental results is given and the growth mechanism of C60 epitaxial films is discussed.
DIELECTRIC AND FERROELECTRIC PROPERTIES OF BaTiO3 THIN FILMS PREPARED BY PULSED LASER DEPOSITION
Authors: LIU YAN-WEI  , ZHANG DAO-FAN  , LI CHUN-LING  , ZHOU YUE-LIANG  , CUI DA-FU  , ZHU YONG  , CHEN ZHENG-HAO  ,   (1)中国科学院物理研究所; (2)中国科学院物理研究所光物理实验室
Published: November 2020

BaTiO3/YBa2Cu3O7-δ bilayer structures have been synthesized on SrTiO3 substrates using the pulsed laser deposition technique. The X-ray analyses show that the BaTiO3 films are highly c-axis oriented. In the studies of dielectric and ferroelectric properties of the BaTiO3 films, typical hysteresis loops and butterfly C-V plots are observed. The results indicate that the BaTiO3 films are promising in FRAM and related application fields.
QUANTUM TRANSPORT THEORY IN METALLIC FILMS
Authors: DONG ZHENG-CHAO  , SHENG LI  , XING DING-YU  , DONG JIN-MING  ,   (1)南京大学物理系; (2)南京大学物理系,固体微结构物理国家重点实验室; (3)南京大学物理系,中国科学院物理研究所磁学国家重点实验室
Published: November 2020

Using Green's function approach and the Kubo formula,have studied the electronic transport in metallic films.Taking into account the quantum size effects and the scattering of impurities and two rough surfaces,we calculate the one-particle Green's functions and the in-plane conductivity.It is found that (1) the density of electrons,the impurity mean free path,and the conductivity in a metallic film show oscillations as a function of its thickness with a period of half the Fermi wavelength;(2) under the approximation of the lowest order in the surface scattering,the conductivity formula obtained can reduce to the quasiclassical result suitable for thick films as well as the previous quantum formula for thin films.
THE TWO-COMPONENT MODEL AND THE JOSEPHSON EFFECT ALONG c-AXIS ON YBCO/Pb JUNCTION
Authors: FENG XIAO-BING  , ZHANG LI-YUAN  , SUN JIU-XUN  ,   北京大学物理系
Published: November 2020

Using the two-component model with the mixing of itinerant carriers and nearly localized carriers with negative -U correlation we study the Josephson effect along c-axis on YBCO/Pb junction.In this model the itinerant carriers have s-wave symmetry and smaller energy gap.The nearly localized carriers have d-wave symmetry and its critical temperature establishes the superconducting transition temperature of the system.the Josephson current is contributed completely by the s-wave.Using the calculated s-wave energy gap and the corresponding critical temperature we have quantitatively explained the product of Josephson current at 0K and junction resistance, Ic(0)RN ,and the variation of Ic with temperature.In addition,we can explain the observed variation of Ic with bias voltage and the Fraunhofer pattern,and the model is consistent with other SQUID experiments probing the symmetry of order parameter of YBCO.Therefore,the two-component model gives a consistent explanation for the two kinds of experimental results which seem to contradict with each other.We also briefly discuss the experimental method which can distinguish different models.
STUDIES OF ELECTRONIC PROPERTIES OF GaS/GaAs INTERFACE
Authors: CHEN XI-YING  , DING XUN-MIN  , ZHANG SHENG-KUN  , ZHANG BO  , LU FANG  , CAO XIAN-AN  , ZHU WEI  , HOU XIAO-YUAN  ,   复旦大学应用表面物理国家重点实验室
Published: November 2020

A novel passivation film on GaAs surface has been grown by microwave sulfur glow discharge technique.Electronic properties of GaS/GaAs interface have been studied by C-V,I-V, and DLTS measurements.C-V measurement shows that the properties of GaS/GaAs interface are nearly ideal and interface state density is about 1012／（cm2·eV),which agrees with result from DLTS measurement.From leak current of MIS′s structure in I-V spectra,the resistivity of GaS is estimated about 1011Ω·cm.
SPONTANEOUS THINNING OF NECKS BETWEEN STM TIP AND THE Pb(110) SURFACE
Authors: GAO BO  , GAI ZHENG  , YANG WEI-SHENG  ,   北京大学物理系人工微结构和介观物理国家重点实验室
Published: November 2020

Recent studies show that the so called “jump to contact” phenomenon, which often happens between a sharp tip and a flat surface in close proximity and results in formation of a neck between the two, is probably the origin of friction. By studying the phenomenon with a scanning- tunneling microscope (STM) and monitoring the conductance evolution, we have found that such necks- between the STM tip and the Pb(110) sample surface, after being stretched to a certain degree, may- shrink spontaneously till its break. The fact that surface cleanness and temperature have- significant influence on the shrinking process suggests that the process is a result of surface- diffusion of Pb atoms.
MOMENTUM TRANSFER BETWEEN QUANTUM FLUID AND THE SOLID SURFACE VIA VORTICES
Authors: WANG CHENG-TAI  , YU LU  ,   (1)国际理论物理中心;中国科学院理论物理研究所; (2)清华大学现代应用物理系
Published: November 2020

The transverse acoustic impedance of an oscillating solid surface in contact with dilute solutions of ３He in 4He is discussed.The calculated values are compared with experiments.A good agreement is achieved.
STUDY ON PROPERTIES OF T* PHASE SUPERCONDUCTING CUPRATES (Bi0.5Sr1.5)(Y,Ce)2Cu2Oy
Authors: ZHANG YONG-JIAN  , CHEN XIAN-HUI  , CAO LIE-ZHAO  ,   中国科学技术大学物理系
Published: November 2020

The optimal synthesis of T* phase superconductors(Bi0.5Sr1.5)(Y,Ce)2Cu2Oy was studied in detail. Slow cooling was required for preparation of single phase T*-type compounds. After quenching,the samples contained Ce2Y2O7 as the major phase without T* structure presented. From room temperature to 1000℃ phase transition was not observed by thermal analysis. Upon slow cooling in oxygen, T*-type cuprates exhibited zero resistance at 30K.
QUANTUM CORRELATION IN FORWARD THREE-WAVE MIXING
Authors: Lv YA-JUN  , WU LING-AN  , WU MEI-JUAN  , LI SHI-QUN  , ZHANG PEI-LIN  ,   (1)清华大学现代应用物理系，北京  100084; (2)中国科学院物理研究所，北京  100080
Published: November 2020

We study the quantum correlation between the signal and pump modes in forward three-wave mixing in media with an intensity-dependent index of refraction, by adopting the semiclassical and the full-quantum theories. Strong positive correlation exists between the two signal modes, but there is strong anti-correlation between the signal modes and the pump. In the semiclassical model, the phase mismatched cases are investigated. In the full-quantum analysis, the effects of the pump quantization and losses are considered.
PREPARATION AND SITE SELECTIVELY EXCITED LUMINESCENCE OF NANOMETRIC SCALE X1-Y2SiO5∶Eu
Authors: YIN MIN  , LOU LI-REN  , ZHANG WEI-PING  , XIA SHANG-DA  , J.C.KRUPA  ,   (1)法国国家科研中心Orsay核物理研究所; (2)中国科学技术大学物理系，合肥  230026; (3)中国科学院长春物理研究所激发态物理开放研究实验室，长春  130021
Published: November 2020

Nanometric Scale X1-Y2SiO5∶Eu was prepared by sol-gel method with particle size about 50nm.The optical properties of the sample were investigated.Its luminescence spectra were recorded at room temperature and 15K using site selective excitation by a dye laser in addition to conventional UV excitation.Site selective excitation gave two sites for the Eu3+ ion in X1-Y2SiO5.These two sites differ significantly from each other as stated by their emission spectra.Wavelengths of the 5D0→7F0—4 transitions of the two sites were tabulated.Lifetimes of the 5D0 energy level were also measured. They are 3.00ms (site 1) and 2.18ms (site 2).
CLASSICAL DYNAMICS OF THREE IONS WITH COLLINEAR CONFIGURATION IN A PAUL TRAP
Authors: SHI LEI  , DUAN YI-WU  , FENG MANG  , ZHU XI-WEN  , FANG XI-MING  ,   (1)中国科学院武汉物理与数学研究所波谱与原子分子物理国家重点实验室，武汉  430071; (2)中国科学院武汉物理与数学研究所波谱与原子分子物理国家重点实验室，武汉  430071;湖南师范大学物理系，长沙  410081
Published: November 2020

We have studied the properties of the classical dynamics of three ions with collinear configuration in a Paul trap.We found that no chaotic motion exists,and the motions of the ions are regular at any given energy E.The trajectories of the ion ensemble in phase space are of the anti-symmetric type and symmetric type periodic(or quasi-periodic) orbits,which are constrained in two KAM tori respectively.The simplest trajectories of the ensemble are periodic orbit A and periodic orbit S.When E tends toward the minimum energy Emin=3.0 of the ensemble,the motions of A orbits and S orbits tend towards the anti-symmetric and symmetric harmonic oscillations,respectively.
PREPARATION OF TWO-MODE SCHR?DINGER-CAT STATES VIA ATOMIC NON-RESONANT INTERACTION WITH TWO-MODE FIELD
Authors: SONG KE-HUI  , GUO GUANG-CAN  ,   (1)怀化师范高等专科学校物理系，湖南怀化  418008;中国科学技术大学物理系和非线性科学中心,合肥  230026; (2)中国科学技术大学物理系和非线性科学中心,合肥  230026
Published: November 2020

A method for the generation of two-mode Schrdinger-cat states via non-resonant interaction of Ξ-type three-level atom with two-mode field is presented.
THEORETICAL ANALYSIS OF THE LASER OUTPUT CHARACTERISTICS IN Er∶YAG CRYSTAL AT 1.6μm WAVELENGTH
Authors: HUANG LI-LEI  , HONG ZHI  ,   (1)浙江大学光电信息工程系，杭州  310027; (2)中国计量学院光电子研究所，杭州  310034
Published: November 2020

The analytical formulas of laser threshold,slope efficiency of a three-energy-level system are deduced from rate-equations of transitions.The absorption cross section of Er3+ ions in YAG crystal is calculated according to measured absorption spectrum.The characteristics of laser at 1.6μm wavelength are analysed.
INVESTIGATION OF TENSILE-STRAINED,LONG WAVELENGTH In1-xGaxAsyP1-y/InP WITH QUANTUM-WELL STRUCTURE BY PHTOLUMINESCENCE MEASUREMENTS
Authors: DING GUO-QING  ,   邮电部武汉邮电科学研究院，武汉  430074
Published: November 2020

The Photoluminescence (PL) Spectra and the double-Crystal X-ray diffraction rocking curves from tensile-strained quantum materials with 2 and 3 wells are reported in this paper.They indicate that PL peaks result from the intrinsic recombination mechanisms between the electrons in the first conducting subband and the holes in the first light,heavy hole subband in the quantum well materials.We have analysed the variation of the twin-peak intensity ratio with temperature theoretically.The calculation result for No.577 and No.572 is basically in agreement with the measured one.The approximate relation of the split value ΔE1 of light-heavy hole subband with the mismatch rate ε is found.The difference of the theoretic calculation value and the measured result for the split value from the first light hole subband and the first heavy hole one is discussed.
SENSITIVITY OF HUMIDITY AND ITS MECHANISM FOR SrTiO3 FILMS DEPOSITED ON SiO2/Si SUBSTRATE
Authors: LI GUAN-QI  , YOU WEN-JUN  , HUANG MEI-QIAN  , ZENG SHAO-HONG  , HUANG ZHAO-HONG  ,   (1)华南理工大学应用物理系，广州  510641; (2)华南师范大学量子电子学研究所，广州  510630
Published: November 2020

A new theoretical model for SrTiO3 physisorption and chemisorption has been developed to quantitatively analyze the effect of relative humidity on electrical conductivity of the amorphous porous SrTiO3 film.This model may also be applied to other type of porous semiconductor ceramics.In this paper,the SrTiO3 film is deposited on SiO2/Si substrate by using the argon-ion beam plating technique,and then formed a planar resistor structure on SrTiO3 film. The experimental results show that, at room temperature,the current decreases slowly when relative humidity changes from 12% to 53%, and then increases rapidly with the increase of relative humidity from 53% to 92%.The current and its rate of change increase with increasing test frequency.The response time of water adsorption is longer than desorption.
CHARACTERISTIC SURFACES OF A UNIFORMLY RECTILINEARLY ACCELERATING KERR BLACK HOLE
Authors: CHENG SU-JUN  , JIANG YA-LING  , YAN RONG-YI  ,   (1)北京师范大学物理系，北京  100875;河南省新乡师范专科学校物理系，新乡  453000; (2)河南省南阳师范专科学校物理系，南阳  473061; (3)湖北省襄阳师范专科学校物理系，襄阳  441053
Published: November 2020

In this paper,we deal with three kinds of characteristic surfaces of a uniformly rectilinearly accelerating Kerr black hole whose mass is varying.i.e., the event horizon,the apparent horizon,and the time-like limit surface (the infinite red-shift surface). It is pointed out that the three kinds of characteristic surfaces no longer coincide with one other when the black hole mass is varying (accreting or evaporating).
A NEW METHOD FOR RAPID SOLIDIFICATION QUENCHING BY RAPID DECOMPRESSION
Authors: HE DUAN-WEI  , ZHANG FU-XIANG  , LIU RI-PING  , ZHANG MING  , XU YING-FAN  , WANG WEN-KUI  ,   中国科学院物理研究所，北京  100080
Published: November 2020

A rapid drop of pressure applied to a melt whose crystallization point is a decreasing function of the pressure may,if the temperature,the initial pressure and the final pressure are appropriately chosen,be equivalent to a rapid thermal quenching.In particular,it may lead to the formation of metastable crystalline or glassy-phase bulk materials.The method might be useful to simulate adiabatic decompressions subsequent to shocks,such as meteorite impacts.The relation between the corresponding cooling rate(Vc) obtained by rapid decompression and the rate of pressure release(Vp) is first given by Vc=KVp,where K is the drop rate of melting point with pressure.This method is evaluated by using Al-Ge system.Our experimental results indicate that quenching with rapid decompression is an effective method for generating corresponding high cooling rate of more than 105K·s-1.
ANALYSIS OF THE NOISE IN VCSEL USING RATE EQUATION
Authors: ZHANG YI  , HUANG YONG-ZHEN  , WU RONG-HAN  ,   中国科学院半导体研究所，北京  100083
Published: November 2020

The noise characteristics of vertical cavity surface emitting laser (VCSEL) are analysed by using rate equations with a reasonable noise simulating method,and the effect of device parameters (such as spontaneous emission factor,output power,injection current and threshold current) on relative intensity noise,frequency noise and spectral linewidth is calculated under single-mode condition.The results are in agreement with experiments.These results may be helpful for optimising the structure design and determing the factors in the application of VCSEL.
STUDY ON HIGH-TEMPERATURE OXIDIZATION OF LOOSELY-ENTANGLED CARBON NANOTUBES PREPARED BY ARC-DISCHARGE
Authors: CHANG BAO-HE  , ZHANG HAO  , ZHOU WEI-YA  , QIAN LU-XI  , PAN ZHENG-WEI  , MAO JIAN-MIN  , LI WEN-ZHI  ,   中国科学院物理研究所，中国科学院凝聚态物理中心，北京  100080
Published: November 2020

A large quantity of loosely-entangled carbon nanotubes was prepared by arc-discharge method. Samples containing the nanotubes were oxidized at high temperatures. The tubes can remain after a relatively long time(over 1h) and high-temperature (of 850℃) oxidization. The amounts of the defect and other structure imperfects might be substantially minimized in the loosely-entangled nanotubes, so the stability of the tubes was greatly improved and the nanotube could have much more opportunities to survive during oxidization. This is consistent with Raman scattering results.
A STUDY OF ANISOTROPY OF THE FINE-STRUCTURE SPLITTINGS OF THE GROUND STATE IN ZnSe∶Fe2+
Authors: LI FU-ZHEN  , ZHOU YI-YANG  ,   (1)四川师范大学固体物理研究所，成都  610066; (2)四川师范大学物理系，成都  610066
Published: November 2020

The Hamiltonian matrices formulae of 5D state for 3d4/3d6 ions in cubic symmetry are derived using a two spin-orbit (SO) coupling parameter model. The Hamiltonian matrices are 25×25(5D) dimensions. On the basis of the formulae, the fine-structure splittings of the ground state in cubic ZnSe∶Fe2+ crystal are calculated. The Zeeman splitting,the Raman shift and the magnetization in magnetic fields up to 30T along the ［100］ and ［111］ directions are investigated, respectively. The present results are in excellent agreement with the experimental ones.
COMPRESSIVE DEFORMATION AND ENERGY ABSORBING CHARACTERISTICS OF FOAMED ALUMINUM
Authors: HAN FU-SHENG  , ZHU ZHEN-GANG  , LIU CHANG-SONG  ,   中国科学院固体物理研究所内耗与固体缺陷开放研究实验室，合肥  230031
Published: November 2020

The deformation and energy absorbing characteristics and mechanisms of foamed aluminum with two different matrixes were investigated through examination of the compressive stress-strain behaviors. It was found that,like other porous solid materials, the stress-strain curve of foamed Al shows distinguished three regions, that is linear elasticity, plastic collapse or brittle crushing and densification. The energy absorbing capacity increases with increasing relative density, and brittle foam exhibits higher capacity than plastic one with the similar yield strength. Foamed Al reaches its peak value of energy absorbing efficiency at relatively lower strain, about 0.15—0.25. With increasing density, the peak values tend to decrease.
STUDY OF TRANSMISSION GRATING DIFFRACTION EFFICIENCIES FOR SOFT X-RAYS
Authors: YANG JIA-MIN  , YI RONG-QING  , CHEN ZHENG-LIN  , SUN KE-XU  , DING YAO-NAN  , ZHENG ZHI-JIAN  , LI CHAO-GUANG  , CUI MING-QI  , ZHU PEI-PING  , CUI CONG-WU  ,   (1)中国工程物理研究院核物理与化学研究所，成都  610003; (2)中国科学院高能物理研究所，北京  100039
Published: November 2020

Absolute diffraction efficiencies of a transmission grating at a photon energy of 844eV have been calibrated on synchrotron radiation source.With the aid of grating model,all structure parameters of the grating are obtained and absolute diffraction efficiencies for soft X-rays in the range of 100—2000eV are calculated and discussed.
POLYMERIZATION OF SOLID C60
Authors: NING DONG  , LOU QI-HONG  ,   中国科学院上海光学精密机械研究所，上海  201800
Published: November 2020

We reviewed recent theoretical and experimental results on the polymerization of solid C60.The characteristics in common of several methods and the difference between each other are analyzed.Orientational disorder always plays an important role in polymerization,because two C60 molecules must be located at a specified relative position before cycloaddition reaction.
ORIENTATIONALLY ORDERED STATE AND REORIENTATION RELAXATION IN SOLID C60 AT HIGH PRESSURE AND LOW TEMPERATURE
Authors: CHEN XIAO-HUA  , PENG JING-CUI  , CHEN KE-QIU  , CHEN ZONG-ZHANG  ,   (1)湖南大学化学化工学院，长沙  410082; (2)湖南大学应用物理系，长沙  410082
Published: November 2020

The distribution of the orientationally ordered structure and reorientation relaxation behavior in solid C60 at high pressure and low temperature have been investigated by using a model of the classical molecular interaction between C60 molecules.The anomalous behavior in thermal conductivity experiment can be well explained theoretically.
INVESTIGATION OF NEUTRALIZED (NH4)2S SOLUTION-PASSIVATED GaAs(100) SURFACES
Authors: YUAN ZE-LIANG  , DING XUN-MIN  , HU HAI-TIAN  , LI ZHE-SHEN  , YANG JIAN-SHU  , MIAO XI-YUE  , CHEN XI-YING  , CAO XIAN-AN  , HOU XIAO-YUAN  , LU ER-DONG  , XU SHI-HONG  , XU PENG-SHOU  , ZHANG  XIN-YI  ,   (1)复旦大学应用表面物理国家重点实验室，上海  200433; (2)中国科学技术大学国家同步辐射实验室，合肥  230019
Published: November 2020

Synchrotron radiation photoelectron spectroscopy (SRPES) combined with scanning electron microscopy (SEM) and gravimetric method is used to study the neutralized (NH4)2S-passivated GaAs(100) surfaces- Compared to the conventional (NH4)2S alkaline solution treatment, a thicker Ga sulfide layer and stronger Ga—S bonding on GaAs surface can be formed by dipping GaAs in neutralized (NH4)2S solution- Gravimetric data show that the etching rate of GaAs in neutralized (NH4)2S solution is about 15% lower than that in the conventional (NH4)2S solution- From SEM observation, only fewer number of etching pits with smaller size on the neutralized (NH4)2S treated GaAs surfaces can be found-
POLARIZATION OF SELF-TRAPPED EXCITON IN POLYMERS UNDER THE ELECTRIC FIELD
Authors: FU ROU-LI  , YE HONG-JUAN  , LI LEI  , FU RONG-TANG  , MIAO JIAN  , SUN XIN  , ZHANG ZHI-LIN  ,   (1)复旦大学李政道物理学综合实验室，物理系，上海  200433; (2)上海大学嘉定分校材料学院，上海  201800; (3)中国科学院上海技术物理研究所红外物理国家重点实验室，上海  200083
Published: November 2020

The self-trapped exciton in polymers under the electric field has been studied using a tight-binding model including the electric field, symmetry-breaking term te and electron-lattice interaction simultaneously. It is discovered that the electric field will polarize the self-trapped exciton in polymers. The polarization depends on the electric field E and te. When te≤0.1eV，self-trapped biexciton in polymers shows the characteristic of the reverse polarization, i.e., electrons move along the direction of E; however, plus charges move along the minus direction of E. The cause of the polarization has been discussed.
INFLUENCE OF Cu DOPING IN Mn SITES OF La-Ca-Mn-O SYSTEM ON MAGNETORESISTANCE EFFECT AT LIQUID NITROGEN
Authors: SUN XIA  , TANG PING  , HUANG ZHEN  , CHEN YUE  , LI GUANG  , CHEN ZHI-YOU  , LIU ZHI-MING  , YUAN SONG-LIU  ,   中国科学院合肥等离子体物理研究所，合肥  230031
Published: November 2020

We studied the influence of Cu doping in Mn sites of single phase bulk materials La2/3Ca1/3Mn1-xCuxOy on their magnetoresistance effect at liquid nitrogen in experiment. We find that, for the best doped sample (x≈0.15), it shows great magnetoresistance effect clearly. Moreover, the main variation of the magnetoresistance is under the field below 1T. The MR ratio rises up to ～5×104% when the field is increased to 6T. It increases three orders of magnitude compared with samples deviated from the best doping.
A STATISTICAL THEORY OF TRANSGRANULAR BRITTLE FRACTURE FOR METALS
Authors: XING XIU-SAN  ,   北京理工大学应用物理系，北京  100081
Published: November 2020

A statistical theory of transgranular brittle fracture for metals is discussed. According to the continuum model of interface energy describing the interaction between transgranular brittle crack and grain boundaries and nonequilibrium statistical theory of fracture,the crack growth rate,fracture strength,fracture toughness,brittle-ductile transition temperature and their statistical distribution functions changing with grain size and interface energy are derived in a unified theory.
SPIN SPLITTING IN PSEUDOMORPHIC InGaAs/InAlAs GRADED HETEROSTRUCTURES AS B→0
Authors: GUI YONG-SHENG  , ZHENG GUO-ZHEN  , GUO SHAO-LING  , CHU JUN-HAO  , TANG DING-YUAN  , CHEN JIAN-XIN  , LI AI-ZHENG  ,   (1)中国科学院上海技术物理研究所红外物理国家重点实验室，上海  200083; (2)中国科学院上海冶金研究所功能材料国家重点实验室，上海  200050
Published: November 2020

The spin splitting in zero magnetic field between the up- and down-spin electrons in a two-dimensional electron gas is obtained for a pseudomorphic InGaAs/In0.52Al0.48As graded heterostructure.We have studied the spin splitting in the heterostructure by means of the Shubnikov-de Haas oscillations.By analyzing the characteristic beating pattern of the oscillations,a spin splitting of 8.76meV was determined as B→0.
SURFACE AND INTERFACES SCATTERING EFFECT ON QUANTUM TRANSPORT IN MULTILAYERED CYLINDRICAL WIRE
Authors: DONG ZHENG-CHAO  ,   淮阴师范学院物理系，淮阴  223001
Published: November 2020

Taking into account the quantum size effects and considering three types of scattering from bulk impurities,rough surface and rough interfaces,we use the quantum-statistical Green's function approach to calculate the conductivity in multilayered cylindrical wire.It is found that in the lowest-order approximation of impurities,surface and interfaces scattering,the total conductivity is given by a sum of conductivities of all the subbands; and the scattering rates for the individual subbands due to the impurities,surface and interfaces are additive.
EXCITON RECOMBINATION DYNAMICS IN CdTe/CdZnTe QUANTUM WELLS
Authors: ZHANG XI-QING  , WANG YONG-SHENG  , XU ZHENG  , HOU YAN-BING  , WANG ZHEN-JIA  , XU XU-RONG  , Z.K.TANG  , WANG HE-ZHOU  , LI WEI-LIANG  , ZHAO FU-LI  , CAI ZHI-GANG  , ZHOU JIAN-YING  ,   (1)Department of Physics,Hong Kong University of Science and Technology,Hong Kong; (2)北方交通大学光电子技术研究所，北京  100044; (3)中山大学超快速激光光谱学国家重点实验室，广州  510275
Published: November 2020

Quantum wells of CdTe/CdZnTe were grown by molecular beam epitaxy. The highest order of satellite peak of the sample is 5 from XRD spectra and excition emission linewidth is about 4.8 nm at 77 K. It was shown that our samples are very good. The recombination dynamics of exciton in high-quality CdZnTe/CdTe multiquantum wells were investigated by means of time-resolved photoluminescence(PL) spectra with different excitation power at 77 K and photoluminescence spectra with different temperature. When weaker excitation was used, radiative recombination decay time of the exciton was reduced as the excitation intensity was decreased; the results indicate that the dominant mechanism may be the quenching of exciton emission by impurities and defects. The linewidth of the exciton emission becomes broader with increasing temperature, the linewidth at low temperature is only due to the well thickness, and the broadening linewidth at high temperature is contributed by the interactions among the exciton and LO and TO phonons and ionized donor impurities. The PL intensities are reduced with increasing temperature, which is mainly due to the thermal dissociation of excitons, i.e., the electrons or holes jump into the barriers from the wells by thermal excitations. The exciton emission from n=2 heavy hole exciton at 77 K has been observed, and the n=2 heavy hole exciton luminescence decay time is shorter than that from n=1. The investigation indicates that there is the exciton energy relaxation from the n=2 to n=1 heavy hole exciton state by phonons.
PROPERTIES OF ELECTRON CYCLOTRON RESONANCE PLASMAS AND THEIR INFLUENCE ON THE DEPOSITION OF GaN FILMS
Authors: DU XIAO-LONG  , CHEN GUANG-CHAO  , JIANG DE-YI  , YAO XIN-ZI  , ZHU HE-SUN  ,   (1)北京理工大学，北京  100081; (2)中国科学院物理研究所，北京  100080; (3)中国科学院物理研究所，北京  100080；北京理工大学，北京  100081
Published: November 2020

Langmuir probes and Faraday cups have been used to characterize electron cyclotron resonance plasmas which have been used in the depositions of GaN films on the substrate of (0001)α-Al2O3.These plasmas were generated with microwave power(Pw) from 300W to 1100W at pressures(p) range from 0.8Pa to 0.05Pa using N2 as the plasma source.The relationship between the plasma parameter,such as ion density(Ni),electron temperature(Te),plasma potential(Vp) and ion current density(Ji),and system parameters,such as pW and p,is given.And the axial and radial distributions of Te,Ni,Vp and Ji are presented.The growth rate and the quality of the GaN film strongly depend on the growth condition.The higher the plasma density,the higher the N/Ga ratio of GaN film.When the microwave power was 850W and gas pressure was 0.22Pa,the plasma near the substrate was characterized by a Te near 1.4eV and plasma density near 2.0×1011 cm-3,and the growth rate of GaN was as high as 0.9μm/h.The full width at half maximum of double-crystal X-ray diffraction rocking curve is 16 arcmin.
THEORETICAL CALCULATIONS OF ISOTHERMAL COMPRESSION CURVES FOR SOLID HELIUM AND SOLID HYDROGEN
Authors: CAI LING-CANG  , LIU FU-SHENG  , JING FU-QIAN  , CHEN DONG-QUAN  ,   (1)北京应用物理与计算数学研究所，北京  100088; (2)西南流体物理研究所冲击波物理与爆轰物理实验室，成都  610003; (3)西南流体物理研究所冲击波物理与爆轰物理实验室，成都  610003；四川联合大学应用物理研究所，成都  610065
Published: November 2020

Based on the atomic cluster theory and quantum mechanics, the isothermal curves of solid helium and solid hydrogen have been calculated. In the calculation for solid hydrogen, the spherical potential approximation suggested by Cui et al. and the effective helium atomic model of ours were adopted. Comparisons of the theoretical results with the avialable experimental data, which are all below 100GPa, were made and it was found that they are in good agreement with each other.
MOLECULAR BIAXIALITY AND THE LOWEST SUPERCOO-LING TEMPERATURE FOR NEMATIC LIQUID CRYSTALS IN ISOTROPIC PHASE
Authors: ZHANG ZHI-DONG  , LIU XIN-DIAN  , HUANG XI-MIN  ,   (1)河北工业大学应用数理系，天津  300130; (2)河北工业大学应用数理系，天津  300130；中国科学院长春物理研究所北方液晶工程研究开发中心，长春  130021; (3)中国科学院长春物理研究所北方液晶工程研究开发中心，长春  130021
Published: November 2020

In the molecular field approximation, we study the effect of molecular biaxiality on the lowest supercooling temperature of nematic liquid crystals in isotropic phase. Theoretical results show that by taking into account the molecular biaxiality, the ratio of the lowest supercooling temperature in isotropic phase T* to the nematic-isotropic phase transition temperature Tc, approaches the experimental value. When the molecular biaxiality parameter δ reaches 0.3, the ratio T*/Tc reaches 0.9817, very close to the experimental value of 0.99.
DYNAMIC SCREENING OF THE (e,2e) PROCESSES FOR LOW-ENERGY ELECTRON IMPACT IONIZATION OF HELIUM
Authors: ZHANG SUI-MENG  , CHEN ZHANG-JIN  , XU KE-ZUN  ,   (1)安徽大学物理系，合肥  230039; (2)六安师范专科学校物理系，六安  237012; (3)中国科学技术大学近代物理系，合肥  230026
Published: November 2020

Based on the modified three-body Sommerfeld parameters,the effective shield of the residual electron in the final state of He+ is further modified for (e,2e) processes- Such a modification represents a dynamic screening of the four bodies in the final state- The triple differential cross sections for electron impact ionization of atomic helium at an incident energy of 50eV in the asymmetric geometry are calculated by use of the modified Sommerfeld parameters-The results were compared with those of the absolute measurements and the only existing theoretical results of the convergent colse-coupling method-It was found that the present results give a better description for the experimental data at fixed ejected energy of 10eV-
ELECTRIC POTENTIAL CALCULATION OF COMPOSITES BY BERGMAN METHOD
Authors: LI XIANG-TING  , MA HONG-RU  ,   上海交通大学应用物理系，上海  200240
Published: November 2020

Using Bergman representation theory,we derived the first principle formulation of electric potential of binary composites,and calculated the electric potential distributions for bct,fcc and bcc structures-
PERTURBATION THEORY FOR SINE-GORDON EQUATION
Authors: TANG YI  , YAN JIA-REN  , ZHANG KAI-WANG  , CHEN ZHEN-HUA  ,   (1)湖南师范大学物理系，长沙  410081; (2)湘潭大学物理系，湘潭  411105; (3)中南工业大学非平衡材料研究所，长沙  410083
Published: November 2020

Making use of the method of multiple scales from the classical perturbation theory and the general method of Laplace transformation from the mathematical physics methods, we have solved the perturbation problem for sine-Gordon equation, and obtained the fist-order correction containing no secular terms, as well as the parameters slowly varied with time-
MAGNETIC PROPERTIES OF Nd-Fe(Co,Nb)-B EXCHANGE COUPLING MAGNET
Authors: WANG YI-ZHONG  , HU JI-FAN  , ZHANG SHAO-YING  , ZHANG HONG-WEI  , SHEN BAO-GEN  ,   (1)山东大学物理系，济南  250100; (2)中国科学院三环公司研究实验室，北京  100080; (3)中国科学院物理研究所国家磁学重点实验室，北京  100080
Published: November 2020

The melt spun ribbons of nanocomposite Nd9Fe85.5-xCoxNb1B4.5(x＝0-16) have been prepared by rapid quenching and post heat treatment. The best magnetic properties obtained in Nd9Fe84.5Nb1B4.5 ribbons are as follows:(BH)max＝156kJ/m3,Jr＝1.11T and μ0HcJ＝0.68T.It is shown that the melt spun ribbons consist of both 2∶14∶1 compound and α-Fe(Co,Nb) phases with mean grain sizes smaller than 30nm. The effect of exchange coupling between the nanostructure grains of Nd2(Fe,Co,Nb)14B and α-Fe(Co,Nb) are observed clearly. The Curie temperature enhancement is about 10K and the largest reduced remanence achieved 0.776.It is also indicated that there is a close relation between the reduced remanence and the mean grain size of α-Fe phase. The smaller the mean grain size of α-Fe phase, the greater the remanence enhancement. The Curie temperature of the melt spun ribbons increases quickly with a rate of 11.3K/at%. The coercivity, remanence and maximum energy product decrease monotonically with increasing Co content for the Nd9Fe85.5-xCoxNb1B4.5 ribbons.
DOUBLE-WAVE DESCRIPTION OF ONE-DIMENSIONAL HYDROGEN ATOM
Authors: HUANG XIANG-YOU  , WANG JI-YE  , YE XUE-MIN  ,   北京大学物理系，北京  100871
Published: November 2020

Stationary solutions of one-dimensional hydrogen atom are two-degree degenerate. Three kinds of typical solutions can be constructed from those degenerated solutions. They correspond to three kinds of ensembles. Double-wave theory describes a single hydrogen atom. When three different averages over ensembles are made for double-wave theory, three kinds of typical solutions in the usual quantum mechanics are obtained. A comparison between these solutions and those of classical mechanics is made.
MODE CORRELATION AND COHERENT-MODE REPRESEN-TATION OF MULTI-MODE LASER BEAMS
Authors: ZHANG BIN  , LV BAI-DA  ,   四川大学激光物理与化学研究所，成都  610064
Published: November 2020

A detailed theoretical study on the mode correlation and coherent-mode representation of multi-mode laser beams has been performed.By using the theory of partially coherent light,the multi-mode laser beams behaving like Gaussian Schell-model(GSM) beams have been represented by the superposition of spatially coherent modes,which may be mutually correlated.The analytical expressions for the mode coherence cofficients have been given in the rectangular coordinate system.Furthermore,based on the M2-factor concept,the theory of the mode decomposition of multi-mode laser beams has been built up for the general case,where the mode correlation is considered.
EFFECTS OF Ce3+ ON PROPERTIES OF THE ～1.6μm WAVELENGTH LASER FROM THE Er3+ DOPED YAG CRYSTAL
Authors: HUANG LI-LEI  ,   中国计量学院光电子研究所，杭州  310034
Published: November 2020

The absorption cross-section of Ce3+ ions in the Ce3+,Er3+∶YAG crystal has been measured.The laser threshold energy (or power) and laser slope efficiency are calculated using a formula deduced from rate equations on the transitions of energy levels.It is shown that the effect of Ce3+ ions in Ce3+,Er3+∶YAG on properties of the laser at ～1.6μm wavelength depends upon the active ion concentration and the length of the crystal rod.The effect of Ce3+ ion is to reduce the laser threshold energy and increase the slope efficiency,when the crystal rod is shorter or the concentration of Er3+ ion is lower.But when the crystal rod is longer or the concentration of Er3+ ion is higher,the effect of Ce3+ ions is on the contrary.
CLASSICAL SIMULATION OF NONSEQUENTIAL IONIZATION IN (ONE DIMENSIONAL) HELIUM ATOM
Authors: QU WEI-XING  , HU SU-XING  , XU ZHI-ZHAN  ,   中国科学院上海光学精密机械研究所强光光学开放研究实验室,上海  201800
Published: November 2020

The nonsequential ionization of one-dimensional helium atom under an intense ultrashort laser pulse is investigated with a classical ensemble theory. Through the dynamic simulation of the average Coulomb potential and the average distance between electron and nucleus, we found that high intensity and long wavelength favour the occurrence of nonsequential ionization for a given duration of pulse.
COMPLETENESS RELATION OF SQUAREN JOST FUNCTIONS TO THE NLS+ EQUATION
Authors: CHEN SHI-RONG  , CHEN XIANG-JUN  ,   (1)暨南大学物理系,广州 510632; (2)武汉大学物理系,武汉 430072
Published: November 2020

Completeness relation of the squared Jost functions to the NLS+ equation is proven by generalized Marchenko equation derived in this note. Hence the direct perturbation theory for dark multi-solitons is performed.
PREPARATION AND TEM STUDY OF BRANCHED CARBON NANOTUBE
Authors: ZHANG XIAO-BIN  , GAN BO  , YANG HANG-XHENG  , QI ZHONG-FU  , LI WEN-ZHU  , ZHANG ZE  ,   (1)浙江大学材料系,杭州 310027；中国科学院凝聚态物理中心北京电子显微镜实验室，北京 100080; (2)浙江大学物理系,杭州 310027; (3)中国科学院凝聚态物理中心北京电子显微镜实验室,北京 100080
Published: November 2020

Branch structure of carbon nanotubes was found in the specimen prepared by pyrolysis of hydrocarbon in two different ways. Morphological and structural aspects of these as-grown tubes were investigated by TEM. The topographic defects related to the branches were discussed and can be considered as a modification for the graphine network.
The Gauss product and Raabe’s integral for k-gamma functions
Authors:   Department of Mathematics, Babes-Bolyai University, Sándor József
Published: November 2020

We obtain an extension of the famous Gauss product formula to the case of k-gamma functions. The Sándor–Tóth short product formula [16] is also attended to these functions. An asymptotic formula and Raabe’s integral analogue are also considered.
Significant role of the specific prime number p = 257 in the improvement of cryptosystems
Authors:   University of Sciences and Technology of Oran, Ali-Pacha Hana , Hadj-Said Naima ,   University of Sciences and Technology of Oran, Ali-Pacha Adda ,   University of Sciences and Technology of Oran, Özer Özen ,   Kırklareli University
Published: November 2020

Cryptology is the significant science which is inseparable from the means of communication of secrets. In a safe manner, it has the main objective of transmitting (potentially sensitive) information between two interlocutors. One distinguishes mainly two “dual” disciplines within cryptology: (a) cryptography, which is interested in the security of information. (b) cryptanalysis, which seeks to attack it. One have a starting set of 256 elements, we add a new element to this set to form a set of 257 elements. In this paper, we consider a finite field that contains 257 elements. As with any field, a finite field is a set on which the operations of multiplication, addition, subtraction and division are defined and satisfy certain basic rules. The most common examples of finite fields are given by the integers modulo p when p is a prime number. For our case ℤ/pℤ, p = 257. We apply it to affine ciphers and show that this cipher looks like a permutation cipher. The idea based on this result, is to use the affine ciphers with the modulo 257 (as an initial permutation) in any specific algorithm of ciphering. Besides, one finishes with the decryption affine with the modulo 257 like an inverse permutation. This is to significantly increase the security of the specific encryption algorithm and to lengthen the 16-bits encryption key.
On the quantity m^2 − p^k where p^k m^2 is an odd perfect number
Authors:   De La Salle University, Manila, Philippines, Dris Jose Arnaldo Bebita , San Diego Immanuel Tobias ,   Trinity University of Asia, Quezon City, Philippines
Published: November 2020

We prove that m^2 - p^k is not a square, if n = p^k m^2 is an odd perfect number with special prime p, under the hypothesis that \sigma(m^2)/p^k is a square. We are also able to prove the same assertion without this hypothesis. We also show that this hypothesis is incompatible with the set of assumptions \big(m^2 - p^k \text{ is a power of two }\big) \land \big(p \text{ is a Fermat prime}\big). We end by stating some conjectures.
A study on some identities involving (sk, t)-Jacobsthal numbers
Authors:   Department of Math., University of Pamukkale, Halici Serpil , Uysal Mine ,   Department of Math., University of Pamukkale
Published: November 2020

In this study, we examined the generalization of Pakapongpun for Jacobsthal numbers. With respect to this generalization, we have given some known basic identities, which have an important place in the literature.
Explicit formula of a new class of q-Hermite-based Apostol-type polynomials and generalization
Authors:   Department of Mathematics, University of UMMTO, Goubi Mouloud
Published: November 2020

The present article deals with a recent study of a new class of q-Hermite-based Apostol-type polynomials introduced by Waseem A. Khan and Divesh Srivastava. We give their explicit formula and study a generalized class depending in any q-analog generating function.