arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0903.3012cond-mat.str-el
收藏

二维哈伯德模型中的两阶段金属-绝缘体相变:8格点动力学集团近似中的动量选择性

Two-stage metal-insulator transition in the 2D Hubbard model: momentum selectivity in the 8-site dynamical cluster approximation

Philipp Werner, Emanuel Gull, Olivier Parcollet, Andrew J. Millis

摘要:

本文用八动量胞的动力学集团近似研究了二维正方晶格哈伯德模型顺磁相的金属-绝缘体相变。我们发现,相互作用驱动和掺杂驱动的过渡是多阶段和动量部门特定的,费米液态金属和完全带隙绝缘体相分离的中间相,其中布里渊区的一些区域是有间隙的,而其他人则维持无间隙准粒子。我们认为,这是一个逐渐缩小的弧或口袋的粗粒度版本。一个明显的粒子-空穴不对称性被发现。

英文摘要:

Metal-insulator transitions in the paramagnetic phase of the two dimensional square lattice Hubbard model are studied using the dynamical cluster approximation with eight momentum cells. We show that both the interaction-driven and the doping-driven transition are multi-stage and momentum-sector specific, with Fermi liquid metal and fully gapped insulator phases separated by an intermediate phase in which some regions of the Brillouin zone are gapped while others sustain gapless quasiparticles. We argue that this is the coarse-grained version of a gradually shrinking arc or pocket. A pronounced particle-hole asymmetry is found.

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。

↑