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1.
AimsandscopeHIGHENERGYPHYSICSANDNUCLEARPHYSICScoversthefieldsofHighEnergyPhysics,Cosmic RayPhysics,HighEnergyAstrophysics,IntermediateEnergyPhysics,NuclearPhysics,HeavyIonPhysics,Accelerator,Detec torandSynchrotronradiationintheaspectsofexperiments,theori…  相似文献   

2.
TheResearchofScatteringCross-SectionandEnergy-ExtractioninFELTheResearchofScatteringCross-SectionandEnergy-ExtractioninFEL¥ZH...  相似文献   

3.
1 INTROEXPERIMENTExperimentalsetupwasshowninFig .1,exhaustivedescriptionsonthesetupandtheprocessofacquiringdatahasalready giveninrelativedocument[1] ,nowwedoexcessivedescriptionnolonger .2 RESULTANDDISCUSSIONResult:earlierspectraoftheplasmaradiatingwereshow…  相似文献   

4.
HIGHENERGYPHYSICSANDNUCLEARPHYSICSisascienceperiodicalfocusingonspecializedfieldswithitsfirstissuepublishedin 1 977.ItissponsoredbytheInstituteofHighEner gyPhysicsandtheInstituteofModernPhysics,theChineseAcademyofSciences.Itisamonthlyjournal,distributedbo…  相似文献   

5.
AnalyticSubjectIndextoVolumeBS,(1996)LASERDEVICESPUlsewidthcharacteristicsofmode-lockedTi:sapphirelaserwithringcaavityKerr-le...  相似文献   

6.
InfluenceonTransmissionPropertiesofSolitonsbyStochasticVariationofSystemParametersandInteractionCHENMinghua;WENYangjin;YANGXi...  相似文献   

7.
ProposalforEfficiencyEnhancementofaFarInfraredFreeElectronLaser¥HUSuxing;FUEnsheng;XUZhizhan(ShanghaiInstiuteofOpticsandFineM...  相似文献   

8.
SERS技术研究电化学中的共吸附顾仁敖(苏州大学化学系苏州215006)SERSStudiesonElectrochemicalCoadsorptionGuRenao(DepartmentChemistry,SuzhouUniversitySuzho...  相似文献   

9.
Analytic Subject Index to Volume B3,(1994)LASERDEVICESNo.Page Vertical--cavitysurface--emittinglasersfabracatedtwicebyimplant...  相似文献   

10.
The Scheme for X-ray Emission Enhancement in Groove TargetTheSchemeforX-rayEmissionEnhancementinGrooveTarget¥WANGXiaofang;XUZ...  相似文献   

11.
王日兴  叶华  王丽娟  敖章洪 《物理学报》2017,66(12):127201-127201
在理论上研究了垂直自由层和倾斜极化层自旋阀结构中自旋转移矩驱动的磁矩翻转和进动.通过线性展开包括自旋转移矩项的Landau-Lifshitz-Gilbert方程并使用稳定性分析方法,得到了包括准平行稳定态、准反平行稳定态、伸出膜面进动态以及双稳态的磁性状态相图.发现通过调节电流密度和外磁场的大小可以实现磁矩从稳定态到进动态之间的转化以及在两个稳定态之间的翻转.翻转电流随外磁场的增加而增加,并且受自旋极化方向的影响.当自旋极化方向和自由层易磁化轴方向平行时,翻转电流最小;当自旋极化方向和自由层易磁化轴方向垂直时,翻转电流最大.通过数值求解微分方程,给出了不同磁性状态磁矩随时间的演化轨迹并验证了相图的正确性.  相似文献   

12.
In order to minimize the effect of the unconsidered frequency components on the generated compression pulse, the phasing-blanking effect is taken into account of designing the one~dimensionai aperiodic domain reversal structure. Hierarchic genetic algorithm for the design of a domain reversal grating to modulate the spectrum and phase of the generated SH pulse simultaneously are presented. Our simulation shows that the quality of an output pulse is fairly improved.  相似文献   

13.
The filamentary fungus Phycomyces blakesleeanus undergoes a series of remarkable transitions during aerial growth. During what is known as the stage IV growth phase, the fungus extends while rotating in a counterclockwise manner when viewed from above (stage IVa) and then, while continuing to grow, spontaneously reverses to a clockwise rotation (stage IVb). This phase lasts for 24-48 h and is sometimes followed by yet another reversal (stage IVc) before the overall growth ends. Here, we propose a continuum mechanical model of this entire process using nonlinear, anisotropic, elasticity and show how helical anisotropy associated with the cell wall structure can induce spontaneous rotation and, under appropriate circumstances, the observed reversal of rotational handedness.  相似文献   

14.
The magnetization and magnetization reversal processes that occur through the mechanism of incoherent rotation of magnetic moments in cubic ferromagnets with limited sizes are investigated theoretically. It is established that the appropriate model representation of magnetic inhomogeneities arising in the region of defects is provided by 0° domain walls. The influence of the external magnetic field on the structure and the stability region of the 0° domain walls is determined. This makes it possible to reveal the characteristic features of the magnetization reversal of real crystals as a function of the material and defect parameters, in particular, in the vicinity of the spin-reorientation phase transition.  相似文献   

15.
We numerically study ultra fast resonant spin torque (ST) magnetization reversal in magnetic tunneling junctions (MTJ) driven by current pulses having a direct current (DC) and a resonant alternating current (AC) component. The precessional ST dynamics of the single domain MTJ free layer cell are modeled in the macro spin approximation. The energy efficiency, reversal time, and reversal reliability are investigated under variation of pulse parameters like direct and AC current amplitude, AC frequency and AC phase. We find a range of AC and direct current amplitudes where robust resonant ST reversal is obtained with faster switching time and reduced energy consumption per pulse compared to purely direct current ST reversal. However, for a certain range of AC and direct current amplitudes a strong dependence of the reversal properties on AC frequency and phase is found. Such regions of unreliable reversal must be avoided for ST memory applications.  相似文献   

16.
A Ramsey interrogation scheme was used to measure the phase shift of laser-cooled 87Rb clock-transition pseudospins arising as a result of a reversal of a bias-magnetic field, i.e., B--> -B, during the interrogation. While no phase shift occurred when the reversal was sudden, the Ramsey fringes were shifted by a factor of pi when the reversal was adiabatic. We thus verified the prediction that the spin states |F,m=0 acquire a purely topological and parity-dependent phase factor of (-1)F as a result of B--> -B.  相似文献   

17.
Employing both null transmission ellipsometry and resonant x-ray diffraction, we confirmed the SmC*FI2-SmC* phase sequence reversal in one liquid crystal compound and specially prepared binary mixtures. This phase sequence reversal was predicted by two recent theoretical advances. Moreover, the temperature range for the SmC*FI2 phase increases significantly in the mixture suggesting that such a phase sequence may exist in other compounds.  相似文献   

18.
In this paper, we focus on better understanding tapping-mode atomic force microscopy (AFM) data of soft block copolymer materials with regard to: (1) phase attribution; (2) the relationship between topography and inside structure; (3) contrast-reversal artifacts; (4) the influence of annealing treatment on topography. The experiments were performed on the surface of poly(styrene–ethylene/butylene–styrene) (SEBS) triblock copolymer acting as a model system. First, by coupling AFM with transmission electron microscopy (TEM) measurements, the phase attribution for AFM images was determined. Secondly, by imaging an atomically flat SEBS surface as well as an AFM tip-scratched SEBS surface, it was confirmed that the contrast in AFM height images of soft block copolymers is not necessarily the result of surface topography but the result of lateral differences in tip-indentation depth between soft and hard microdomains. It was also found that there is an enlarging effect in AFM images on the domain size of block copolymers due to the tip-indention mechanism. Thirdly, based on the tip-indention mechanism, tentative explanations in some detail for the observed AFM artifacts (a reversal in phase image followed by another reversal in height image) as function of imaging parameters were given. Last, it was demonstrated that the commonly used annealing treatments in AFM sample preparation of block copolymers may in some cases lead to a dramatic topography change due to the unexpected order-to-order structure transition.  相似文献   

19.
The quantized electronic structure in Pb films on Si(111) varies substantially as the film thickness increases. The changes in electronic energy cause the thermal stability of the films to oscillate with an approximate bilayer period. The phase of the oscillations can be controlled by interfacial engineering. Comparison of Pb films prepared on Si(111) terminated by In, Au, and Pb as interfactants reveals a phase reversal. For , films made of odd numbers of atomic layers (5, 7, and 9) are more stable than the even ones. This trend is reversed for the other two cases.  相似文献   

20.
张洪波  张希仁 《物理学报》2018,67(5):54201-054201
抑制散射介质对光的散射,调控光在散射介质中的传输,是光通信、生物光子学、光镊等领域的重要课题.设计并实现了基于宽谱光源和数字相位共轭的可调控光在散射介质中传输的时间反演实验系统.实验获取了不同相干长度下物光和参考光束之间的光程差与干涉图样、相位图及时间反演信号之间的关系,分析了光源相干性对调控光在散射介质中传输的影响.实验结果表明,基于宽谱光源的相干特性和数字相位共轭技术,通过调节光程差能选择性获取同一散射角度及相同传输路径的光束的相对相位,再利用空间光调制器对参考光束进行调控,实现光束的反向传播,从而选择性实现对同一散射角度及相同传输路径的光的时间反演.  相似文献   

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