论文标题
掺杂$ 2D $ Hubbard模型的非弗米液体制度的熵
Entropy in the non-Fermi-liquid regime of the doped $2d$ Hubbard model
论文作者
论文摘要
我们研究了掺杂的哈伯德模型在平方晶格上的热力学特性，在金属对绝缘体交叉附近的低温和自旋波动方面，并使用图表限制中直接在热力学极限中直接使用图解的蒙特卡洛方法来获得控制结果。熵的行为揭示了在足够高的相互作用的相互作用上的非纤维流动状态：随着耦合强度的提高，非零掺杂的熵的最大值与拐点以及一个拐点一起发展，表明金属将金属变成非纤维 - 富特液体的交叉。特定的热量表现出非弗米液体状态的其他独特特征。因此，熵的测量可以用作光学晶格中超低原子的量子模拟实验中系统状态的探测。
We study thermodynamic properties of the doped Hubbard model on the square lattice in the regime of strong charge and spin fluctuations at low temperatures near the metal-to-insulator crossover and obtain results with controlled accuracy using the diagrammatic Monte Carlo method directly in the thermodynamic limit. The behavior of the entropy reveals a non-Fermi-liquid state at sufficiently high interactions near half-filling: a maximum in the entropy at non-zero doping develops as the coupling strength is increased, along with an inflection point, evidencing a metal to non-Fermi-liquid crossover. The specific heat exhibits additional distinctive features of a non-Fermi-liquid state. Measurements of the entropy can therefore be used as a probe of the state of the system in quantum simulation experiments with ultracold atoms in optical lattices.
