Magnetic excitations of diagonally coupled checkerboards

来源 :中国物理B(英文版) | 被引量 : 0次 | 上传用户:sangsang126
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
By using quantum Monte Carlo based stochastic analytic continuation(QMC-SAC)and spin wave theory,we study magnetic excitations of Heisenberg models with diagonally coupled checkerboard structures.We consider three kinds of checkerboard models(DC 2×2,DC 3×3,and CDC 3×3)consisting nearest-neighbor strong J1 and weak J2 antiferro-magnetic interactions.When the coupling ratio g=J2/J1 approaches 1,all three diagonal checkerboards have the same long-range antiferromagnetic Néel order at T=0.When g decreases,the quantum fluctuation can drive DC 2×2 model to quantum paramagnetic state,while DC 3×3 and CDC 3×3 models still have the long-range Néel order.By calculating the magnetic excitations at different coupling ratios,we find that the low-energy part of magnetic excitations calculated by QMC-SAC can be well explained by the spin wave theory.However,the high-energy parts even deep in the long-range an-tiferromagnetic phase are beyond the spin wave description.Compared to the g=1 uniform square lattice,the high-energy excitations are more rich in our models.Our study may also draw the attention to the high-energy exctitaions beyond the spin wave theory.
其他文献
A multilayered spin valve film with a structure of Ta(5 nm)/Co75Fe25(5 nm)/Cu(2.5 nm)/Co75Fe25(5 nm)/Ir20Mn80(12 nm)/Ta(8 nm)is prepared by the high-vacuum direct current(DC)magnetron sputtering.The effect of temperature on the spin valve structure and th
The injection of a self-avoiding flexible polymer into a spherical cavity under a driving force is studied by using Langevin dynamics simulation.For given polymer length(N)and driving force(f),the polymer can be completely injected into the cavity only wh
DNA/GO composite plays a significant role in the research field of biotechnology and nanotechnology,and attracts a great deal of interest.However,it is still unclear how the oxidation degree of the graphene-based surface affects the adsorption process of
乳蛋白是天然动物奶的主要成分,具有高营养、易吸收、增强免疫力、抗氧化等多种生物活性.采用基因工程和细胞工厂等技术手段,高效表达天然奶中的各种乳蛋白组分,已成为当前人造奶生物合成的研发热点和技术难点.人造奶作为一个已商业化面向市场并正在改变世界的新兴科技食品,营养风味与天然牛奶相当,但不含乳糖、胆固醇、抗生素和致敏原等不良因子,其生产过程无需养殖动物,可以有效节约资源与能源,是一种颠覆传统养殖业的未来乳制品生产新模式,将引领未来食品产业和细胞农业发展方向.本文系统总结了模式微生物底盘改造、重组乳蛋白高效表达
The single-phase multiferroic Bi5Fe1-xNixTi3O15(BFNT-x,x=0,0.1,0.2,0.3,0.4,and 0.5)ceramics were syn-thesized by a sol-gel auto-combustion method,and their microstructures,ferroelectric,magnetic,and dielectric properties were investigated in detail.All sa
The role of the oxygen in AlGaN/GaN high electron mobility transistors(HEMTs)before and after semi-on state stress was discussed.Comparing with the electrical characteristics of the devices in vacuum,air,and oxygen atmosphere,it is revealed that the oxyge
Based on the transport theory and the polarization relaxation model,the effects of hydrogen and hydroxyl passivation on the conductivity and dielectric properties of silicon carbide nanowires(SiCNWs)with different sizes are numerically simulated.The resul
Recently rare-earth chalcogenides have been revealed as a family of quantum spin liquid(QSL)candidates hosting a large number of members.In this paper we report the crystal growth and magnetic measurements of KErTe2,which is the first member of telluride
在人口老龄化背景下,老年人的健康问题日益凸显,老年人对医疗与养老的双重需求越来越显著,其生活质量有待提高.本文综述了国内外学者对医养结合、老年人生活质量等相关概念及理论,对医养结合模式下的老年人生活质量进行研究,旨在探索出一条适合我国国情的医养结合养老新模式,以期提高老年人的健康水平和生活质量.
天然产物一直以来都是药物先导化合物的重要来源.在药物发现领域,基因组数据常用来识别潜在的药物靶点或寻找先前被忽视的天然产物的生物合成基因簇.尽管基因组测序发现了微生物和植物中存在大量未开发的化学多样性,然而,仅仅利用传统的分离分析方法获取新的天然产物已经无法满足药物发展的需求.随着基因组时代的到来,数字化的基因组挖掘已经成为天然产物发现的重要组成部分.伴随着高通量测序方法的发展和DNA数据的丰富,各种基因组挖掘方法和工具被开发出来,以指导发现和表征这些天然产物.本文综述了近年来基因组挖掘的网络工具、数据库