Abstract: The authors investigate the phase diagram of a frustrated spin ladder model with four-spin ring exchange by bosonization technique and renormalization group method. After having taken effects of quantum fluctuations into account, the phase diagram of the system becomes very complicated. Besides the existences of Haldane phase, rung-singlet phase and the staggered dimerized (SD) phase, there is a columnar dimerized (CD) phase emerging.

Key words: spin ladder model, four-spin ring exchange, dimerized phase, bosonization

摘要： 利用玻色化方法和重整化群技术, 研究了一个具有四自旋交换作用以及链间次近邻阻挫相互作用的自旋梯子模型的相图。在考虑了量子涨落效应以后, 发现体系的相图变得非常复杂。除了存在所谓Haldane相和Rung-Singlet相以及它们之间的SD型二聚化(staggered dimerized)相之外, 亦可能出现一个新的CD型二聚化 (columnar dimerized)相。

关键词: 自旋梯子模型, 四自旋交换作用, 二聚化相, 玻色化方法