LOW-LYING EXCITATIONS IN THE HALF-FILLED AND DOPED HUBBARD-MODEL IN ONE DIMENSION

被引:2
作者
KUSAKABE, K
AOKI, H
机构
[1] Department of Physics, University of Tokyo, Hongo
来源
PHYSICAL REVIEW B | 1991年 / 44卷 / 15期
关键词
D O I
10.1103/PhysRevB.44.7863
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Dispersions and wave functions of all the low-lying excitations are studied numerically along with the Bethe-ansatz analysis for the finite-U one-dimensional Hubbard model for U = 0 --> U = infinity. We find the following. (i) In addition to conventional charge or spin excitations such as des Cloizeaux-Pearson modes, there are classes of excitations involving both spin and charge degrees of freedom. These include the heavy-mass modes arising from the Doucot-Wen gauge potentials. (ii) As U is increased, some level crossings take place at a crossover region of U approximately 10t in which low-lying spin- and charge-excitation bands become separated and the antiferromagnetic spin correlation becomes significant. (iii) For systems doped with more than one hole, the heavy-mass modes split into branches.
引用
收藏
页码:7863 / 7869
页数:7
相关论文
共 26 条
[1]  
[Anonymous], 1962, PHYS REV, DOI DOI 10.1103/PHYSREV.128.2131
[2]   SUPERCONDUCTIVITY IN A 2-BAND HUBBARD-MODEL [J].
AOKI, H ;
KUROKI, K .
PHYSICAL REVIEW B, 1990, 42 (04) :2125-2136
[3]   EXCITATION SPECTRUM OF ONE-DIMENSIONAL HUBBARD MODEL [J].
COLL, CF .
PHYSICAL REVIEW B, 1974, 9 (05) :2150-2158
[4]   INSTABILITY OF THE NAGAOKA STATE WITH MORE THAN ONE HOLE [J].
DOUCOT, B ;
WEN, XG .
PHYSICAL REVIEW B, 1989, 40 (04) :2719-2722
[5]   WHAT IS THE SPIN OF A SPIN-WAVE [J].
FADDEEV, LD ;
TAKHTAJAN, LA .
PHYSICS LETTERS A, 1981, 85 (6-7) :375-377
[6]   SYMMETRY STUDIES OF ANTIFERROMAGNETIC HEISENBERG-MODEL [J].
ISHINO, T ;
SAITO, R ;
KAMIMURA, H .
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 1990, 59 (11) :3886-3897
[7]   LUTTINGER ANOMALY EXPONENT OF MOMENTUM DISTRIBUTION IN THE HUBBARD CHAIN [J].
KAWAKAMI, N ;
YANG, SK .
PHYSICS LETTERS A, 1990, 148 (6-7) :359-362
[8]   CHARGE EXCITATIONS IN THE ONE-DIMENSIONAL HUBBARD-MODEL [J].
KAWAKAMI, N ;
OKIJI, A .
PHYSICAL REVIEW B, 1989, 40 (10) :7066-7072
[9]   SPIN-WAVE RENORMALIZATION IN 2-DIMENSIONAL ANTIFERROMAGNETS WITH FINITE HOLE DENSITY [J].
KO, DYK .
PHYSICAL REVIEW LETTERS, 1990, 65 (01) :116-119
[10]  
KUSAKABE K, UNPUB