“禁忌”3-磁振子相互作用哈密顿项的有效性分析

考察磁有序晶体中局部存在的动量守恒而能量不守恒的3-磁振子激励过程，通过幺正变换，把自旋波理论中不合理的3-磁振子产生与湮没过程的哈密顿项构造为有 效的4-磁振子相互作用哈密顿项. 关键词： 磁振子 哈密顿项 幺正变换     

试评高考"3+综合"模式

高考"3+综合"模式,对中学物理教师提出了更新更高的要求:要教好物理课,仅仅精通物理学科各部分的知识,懂得教育学、心理学和教学法还不够.教学是一种综合艺术,由于新世纪科学技术突飞猛进和知识经济迅速发展需要大量的复合型、创新型人才,综合科目考试要求学生有较高的运用多学科知识综合分析和解决问题的能力.     

Quantum frustration in the "spin liquid" phase of two-dimensional 3He

We have measured the ultralow temperature and low field magnetic susceptibility of the 4/7 phase of two-dimensional 3He adsorbed on graphite preplated by one layer of 4He. The experiments are performed by progressively adding 4He to the system, thus suppressing in a controlled way the 3He atoms trapped in substrate heterogeneities. This procedure enables us to determine the intrinsic properties of this spin 1/2 model magnet in the zero field limit. The results show quantitatively that the system is strongly frustrated by multiple spin exchange interactions. A characteristic gapped spin liquid behavior is observed at ultralow temperature.