Theoretical Studies of Superconductors and Superfluids

本提案所包含的研究将探讨几种显示宏观量子特性的系统的低温理论行为。劳克林最近提出，服从半分数统计的粒子会表现出超导性。他们将继续对高tc超导体的这个模型进行研究，重点是在零温度和有限温度下的激发谱和排斥短程电位的影响、远程规范力的筛选以及对外部磁场的响应。利用轨道动力学的流体动力学模型研究了超流体3He-A中进动耗散畴壁的行为，特别关注了这些动态结构的稳定性、对外部磁场的响应以及偶极子解锁的影响。准经典的形式主义将被用来扩展他们以前的研究超流体3He在严格限制的几何超出金兹堡-朗道制度。他们最初计划分析平面边界，但他们最终寻求将通过收缩的流动作为薄弱环节的模型。

The research included in this proposal will investigate the low- temperature theoretical behavior of several systems that display macroscopic quantum properties. Laughlin has recently suggested that particles obeying half fractional statistics would exhibit superconductivity. They will continue their study of this model for high-Tc superconductors, focusing on the excitation spectrum and the effect of a repulsive short-range potential, the screening of the long-range gauge forces, and the response to an external magnetic field, both at zero temperature and at finite temperature. The behavior of precessing dissipative domain walls in superfluid 3He-A will be investigated with the hydrodynamic model of orbital dynamics, with particular attention to the stability of these dynamic textures, the response to external magnetic fields, and the effect of dipole unlocking. The quasi- classical formalism will be used to extend their previous studies of superfluid 3He in severly confined geometries beyond the Ginzburg-Landau regime. They initially plan to analyze planar boundaries, but they eventually seek to treat flow through a constriction as a model for a weak link.