ELECTROMAGNETIC MESOSCOPIC MODEL IN CONTINUOUS MEDIA

从1995年到1998年，我们从实验和数值两方面对介观现象进行了研究，并考虑了其工程应用。主要研究结果如下：（1）利用有限Larmor半径-磁流体模型和回旋流体模型研究了介观等离子体中电磁波与粒子之间的朗道阻尼和共振机制。此外，本文还利用超粒子模型在并行计算机上模拟了离子-电子双流不稳定性，并利用MHD模型研究了负剪切作用下托卡马克等离子体的稳定性。(2)求解了微磁学的朗道-利夫希茨-吉尔伯特方程，提出了电磁计算中的磁滞模型。此外，我们还对自旋极化STM和交换力显微镜进行了研究，并用新的边界元方法分析了三维磁屏蔽问题。(3)用量子线中电子波的运动模拟了磁场中二维电子气的弹道现象。从量子信息、量子计算和多粒子态的角度讨论了量子计算机的概念. (4)发展了第二类超导体的介观本构模型，并对其进行了数值研究，以便用于空间设备和电磁器件的设计和分析。(5)提出了非线性光波导的有限元光束传播法，研制了光存储系统，应用了声光互作用系统，并进行了空间相干性改变光谱的实验研究。

From 1995 to 1998, we studied on mesoscopic phenomena from view point of experimental and numerical aspect and considered its engineering application. Results are summarized as follows,(1) FLR (finite Larmor radius) - MHD (magnetohydrodynamics) model and gyro-fluid model are applied to understand the mechanism of the Landau damping and resonance between electromagnetic waves and particles in mesoscopic plasmas. In addition, super particle models are used to simulate an ion-electron two - stream instability with a parallel computer and MHD models are applied to study on a stability for tokamak plasmas with the negative shear.(2) We solved the Landau - Lifshitz - Gilbert equation for micromagnetics and presented hysteresis models in electromagnetic computation. And also, we studied on spin - polarized STM and exchange force microscopy, and analyzed 3 - D magnetic shield problems by using new BEM method.(3) Phenomena exhibited by ballistic 2 - D electron gas in magnetic fields were simulated as motion of electron waves in quantum wires. Concept of quantum - mechanical computers was discussed from view point of quantum information, computation, and multiparticle states.(4) Mesoscopic constitutive modes in type - II superconductors were developed and studies numerically, so that they were used in design and analysis of space equipments and electro - magneto devices.(5) Propose of finite element beam propagation method for nonlinear optical waveguides, development of optical memories system, application of acoustic - optic interaction systems, and experiments on a change in optical spectrum by spatial coherence have been done.