arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0705.2937cond-mat.str-elcond-mat.supr-con
收藏

t-J模型的掺杂载流子表述:投影约束和有效的Kondo-Heisenberg格点表示

Doped carrier formulation of the t-J model: the projection constraint and the effective Kondo-Heisenberg lattice representation

Rafael T. Pepino, Alvaro Ferraz, Evgueny Kochetov

摘要:

我们表明,最近提出的掺杂载流子的t-J模型的哈密顿公式应补充的约束,项目的非物理状态。有了这个新的重要成分,以前使用的和看似不同的自旋费米子表示的t-J模型被证明是规范相关的。这种新的约束可以被视为在一个可控的方式接近半填充,这表明掺杂载流子表示提供了一个适当的理论框架,以解决在这个区域中的t-J模型。这个约束也表明,t-J模型可以映射到一个Kondo-Heisenberg晶格模型。这种映射突出了准二维重费米子和高温$_c$超导体之间重要的物理相似性。最后,我们讨论了我们的模型表示的物理意义,特别是小与大费米表面交叉的晶格自旋间隙的关闭。

英文摘要:

We show that the recently proposed doped carrier Hamiltonian formulation of the t-J model should be complemented with the constraint that projects out the unphysical states. With this new important ingredient, the previously used and seemingly different spin-fermion representations of the t-J model are shown to be gauge related to each other. This new constraint can be treated in a controlled way close to half-filling suggesting that the doped carrier representation provides an appropriate theoretical framework to address the t-J model in this region. This constraint also suggests that the t-J model can be mapped onto a Kondo-Heisenberg lattice model. Such a mapping highlights important physical similarities between the quasi two-dimensional heavy fermions and the high-T$_c$ superconductors. Finally we discuss the physical implications of our model representation relating in particular the small versus large Fermi surface crossover to the closure of the lattice spin gap.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑