该研究团队采用可控的图解蒙特卡罗计算方法，研究了有限温度下的掺杂二维哈伯德模型，从而能够在无限大系统极限和任意动量分辨率下计算光谱特性。
研究人员发现，根据掺杂程度和相互作用强度，存在三种不同的状态：弱相关金属、具有强相互作用效应的相关金属以及低掺杂下的赝能隙状态。
研究人员证明，无论是在弱耦合（此时磁相关长度较大）还是在强耦合（此时磁相关长度较短）情况下，都会形成赝能隙。随着温度降至零，赝能隙状态精确外推至基态方法所发现的条纹有序相。
据悉，赝能隙与基础基态相之间的关系尚未得到严格确立。
附：英文原文
Title: Origin and fate of the pseudogap in the doped Hubbard model
Author: Fedor SimkovicIV, Riccardo Rossi, Antoine Georges, Michel Ferrero
Issue&Volume: 2024-09-20
Abstract: The relationship between the pseudogap and underlying ground-state phases has not yet been rigorously established. We investigated the doped two-dimensional Hubbard model at finite temperature using controlled diagrammatic Monte Carlo calculations, allowing for the computation of spectral properties in the infinite-size limit and with arbitrary momentum resolution. We found three distinct regimes as a function of doping and interaction strength: a weakly correlated metal, a correlated metal with strong interaction effects, and a pseudogap regime at low doping. We show that the pseudogap forms both at weak coupling, when the magnetic correlation length is large, and at strong coupling, when it is shorter. As the temperature goes to zero, the pseudogap regime extrapolates precisely to the ordered stripe phase found by ground-state methods.
Source: https://www.science.org/doi/10.1126/science.ade9194