Nematic phase in a two-dimensional Hubbard model at weak coupling and finite temperature
Nematic phase in a two-dimensional Hubbard model at weak coupling and finite temperature
复制标题
DOI：
10.1103/physrevb.98.075126
复制
发表时间：
2018-03
影响因子：
3.7
通讯作者：
S. Slizovskiy;P. Rodriguez-Lopez;J. Betouras
中科院分区：
文献类型：
--
作者：
S. Slizovskiy;P. Rodriguez-Lopez;J. Betouras
我们将自洽重正化微扰理论应用于有限温度下方晶格的哈伯德模型，以研究费米面（FS）随温度和掺杂的变化。此前，据报道，同一模型的向列相在零温度下从闭合FS到开放FS的Lifshitz转变附近的弱耦合处出现，其中自洽重正化微扰理论被证明对FS的小变形敏感。 We find that the competition with the superconducting order leads to a maximal nematic order appearing at nonzero temperature.我们明确地观察到向列不稳定开始时的两个竞争相，并通过比较大正则势，我们发现转变是一阶的。我们解释了具有多个对称相关范霍夫点的系统中相互作用驱动的自发对称性破缺到向列相的起源，并讨论了所需的条件。
We apply the self-consistent renormalized perturbation theory to the Hubbard model on the square lattice at finite temperatures to study the evolution of the Fermi surface (FS) as a function of temperature and doping. Previously, a nematic phase for the same model has been reported to appear at weak coupling near a Lifshitz transition from closed to open FS at zero temperature where the self-consistent renormalized perturbation theory was shown to be sensitive to small deformations of the FS. We find that the competition with the superconducting order leads to a maximal nematic order appearing at nonzero temperature. We explicitly observe the two competing phases near the onset of nematic instability, and by comparing the grand canonical potentials, we find that the transitions are first order. We explain the origin of the interaction-driven spontaneous symmetry breaking to a nematic phase in a system with several symmetry-related Van Hove points and discuss the required conditions.