太阳风等离子体输出流量的全日面二维结构

本文根据1983年十个 Carrington 周(1733—1742)期间的 K-日冕亮度、行星际闪烁(IPS)观测和光球磁场观测,首次探讨了太阳风等离子体质量、动量和能量输出流量 F_M,F_P 和 F_E 的全日面二维平均结构及其与光球磁场结构的关系.     

Singlet-Triplet Transition in Quantum Dots Confined by Triangular and Bowl-Like Potentials： the Effect of Electric Fields

We theoretically investigate the energy spectra of two-electron two-dimensional （2e 2D） quantum dots （QDs） confined by triangular potentials and bowl-like potentials in a magnetic field by exact diagonalization in the framework of effective mass theory. An in-plane electric field is found to contribute to the singlet-triplet transition of the ground state of the 2e 2D QDs confined by triangular or bowl-like potentials in a perpendicular magnetic field. The stronger the in-plane electric field, the smaller the magnetic field for the total spin of the ground states in the dot systems to change from S = 0 to S = 1. However, the influence of an in-plane electric field on the singlettriplet transition of the ground state of two electrons in a triangular QD modulated by a perpendicular magnetic field is quite small because the triangular potential just deviates from the harmonic potential well slightly. We find that the strength of the perpendicular magnetic field needed for the spin singlet-triplet transition of the ground state of the QD confined by a bowl-like potential is reduced drastically by applying an in-plane electric field.     

用激光吹气注入高Z杂质使HL-1M装置放电有效地安全终止的研究

现在国际上大装置纷纷发现破裂放电而导致电流突然中止造成装置遭受重大的危害，因为能量熄灭阶段存在强烈的热通量，而且在电流熄灭阶段中产生强烈的逃逸电子，使得第一壁材料可运行的时间大大缩减；同时在真空器壁上产生很强的电磁力。所以，必须在大装置上建立一种避免和软化能量衰竭与电流衰竭，并且控制预计的放电破裂或突然终止放电的措施。     

Effect of Guiding Magnetic Field on Weibel Instability

We derive a linear dispersion relation in the presence of a constant uniform guiding magnetic field parallel to the beam velocity direction, which shows a strong background magnetic field suppresses or even stabilizes the Weibel instability produced by two counter streams in electron-ion plasmas. The simulation results are in good agreement with the analytical ones. Also observed in the simulations are the suppression of electrostatic field, a higher level of saturation of self-generated magnetic field, and the apparent difference in phase space compared with those in the absence of guiding magnetic field.     

恒定磁场中物质的能量密度

本讨论了在恒定磁场中移入有限体积的物质后磁场中能量的变化，并导出了恒定磁场中的物质的能量密度表达式。     

闭合回路在磁场中的运动

1载流圆环在匀强磁场中的受力情况 半径为r0,通以电流I的弹性圆环,放在光滑的水平面上,磁感强度为B0的匀强磁场垂直穿过圆环,如图1所示.     

原子磁芯片与量子回路

 在过去几年中,物理学家们研究出了多种可把原子云团冷却到温度低于1微开(μK)的技术。处于这些云团中的原子是如此之冷,以至于它们不能再被看作是遵守牛顿定律的经典粒子,而应被看作是由量子力学所描述的可传播、衍射和相互干涉的波。现在,人们已经可以把冷原子囚禁在横向尺寸只有100纳米的量子点内,也可使之在长的狭管中流动,就像电子在很细的导线中流动一样。人们开始注意到一种全新的技术的可能性,这一技术与微电子技术相类似,只是它基于受控冷原子流及原子之间的相互作用。这种被称为“原子芯片”的器件可以利用量子力学原理来完成非同寻常的测量或计算工作。