Mixed spin ladders with exotic ground states

被引：8
作者：
Kolezhuk, AK
Mikeska, HJ
机构：
[1] Univ Hannover, Inst Theoret Phys, D-30167 Hannover, Germany
[2] Inst Magnetism, UA-252142 Kiev, Ukraine
来源：
EUROPEAN PHYSICAL JOURNAL B | 1998年 / 5卷 / 03期
关键词：
D O I：
10.1007/s100510050475
中图分类号：
O469 [凝聚态物理学];
学科分类号：
070205 ;
摘要：
We study the "mixed spin" isotropic ladder system having S = 1 spins on one leg and S = 1/2 spins on the other, with general-type exchange interactions between spins on neighboring rungs. A set of model Hamiltonians with exact ground states in the form of a certain matrix product wave function is obtained. We show that sufficiently strong frustration can lead to exotic singlet ground states with infinite (exponential) degeneracy. We also list a couple of rather simple models with nontrivial ground states, including a model with only bilinear exchange.
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收藏
页码：543 / 550
页数：8
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