Spectral function for the S=1 Heisenberg antiferromagetic chain

作     者：Steven R. White Ian Affleck 

作者机构：Department of Physics and Astronomy University of British Columbia Vancouver British Columbia Canada V6T 1Z1 

出 版 物：《Physical Review B》 (Phys. Rev. B Condens. Matter Mater. Phys.)

年 卷 期：2008年第77卷第13期

页      面：134437-134437页

核心收录：

学科分类：0808[工学-电气工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：National Science Foundation, NSF, (0605444) National Science Foundation, NSF 

摘      要：We study the spectral function S(k,ω) for the spin-1, one dimensional antiferromagnetic chain using a time-dependent density matrix renormalizaton group numerical method. We develop methods for extrapolating the time-dependent correlation functions to larger times in order to enhance the frequency resolution. The resulting spectral functions are impressively precise and accurate. Our results confirm many qualitative expectations from nonlinear σ model methods and test them quantitatively. The critical wave vector at which the single particle excitation emerges from the two-particle continuum is estimated to be 0.23π–0.24π.