ELECTROMAGNETIC MESOSCOPIC MODEL IN CONTINUOUS MEDIA

1995年至1998年，从实验和数值两方面对细观现象进行了研究，并考虑了其工程应用。(1)应用FLR (finite Larmor radius) - MHD （magnetohydrodynamics）模型和陀螺流体模型来理解介观等离子体中电磁波与粒子之间的朗道阻尼和共振机理。此外，利用超粒子模型在并行计算机上模拟了离子-电子两流不稳定性，并应用MHD模型研究了负剪切托卡马克等离子体的稳定性。(2)求解了微磁学的Landau - Lifshitz - Gilbert方程，给出了电磁计算中的磁滞模型。此外，我们还研究了自旋极化STM和交换力显微镜，并采用新的边界元法分析了三维磁屏蔽问题。(3)将弹道二维电子气在磁场中的运动模拟为量子线中电子波的运动。从量子信息、量子计算和多粒子态的角度讨论了量子力学计算机的概念。(4)对II型超导体的介观本构模式进行了数值研究，可用于空间设备和电磁器件的设计与分析。(5)提出了非线性光波导的有限元光束传播方法，开发了光存储系统，在声光相互作用系统中的应用，进行了空间相干对光谱变化的实验。

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.