论文标题
量子物质的激发光谱II：随机$ t $ - $ J $型号
Excitation spectra of quantum matter without quasiparticles II: random $t$-$J$ models
论文作者
论文摘要
我们介绍了$ t $ - $ J $模型的光谱函数的数值解决方案，并随机和全能交换以及全局SU（$ M $）旋转旋转对称性。解决方案是从大容量限制的鞍点方程中获得的，其次是$ M $限制。这些鞍点方程涉及Green的功能，用于携带紧急U（1）量规电荷的分数化旋转子和圆顶子，遵守与Sachdev-Ye-Kitaev（Syk）模型相似的关系。将低频频谱函数与对操作员缩放维度的分析分析进行了比较，并具有良好的一致性。我们还计算了仪表不变的可观察物的低频和温度行为：电子绿色的功能，局部自旋敏感性和光导电导率；以及D.C的温度依赖性电阻率。时间重新聚集软模式（相当于二维量子重力的全息双重模型中的边界重力）对所有可观察到的物质做出了重要的贡献，并为D.C提供了线性的温度贡献。电阻率。
We present numerical solutions of the spectral functions of $t$-$J$ models with random and all-to-all exchange and global SU($M$) spin rotation symmetry. The solutions are obtained from the saddle-point equations of the large volume limit, followed by the large $M$ limit. These saddle point equations involve Green's functions for fractionalized spinons and holons carrying emergent U(1) gauge charges, obeying relations similar to those of the Sachdev-Ye-Kitaev (SYK) models. The low frequency spectral functions are compared with an analytic analysis of the operator scaling dimensions, with good agreement. We also compute the low frequency and temperature behavior of gauge-invariant observables: the electron Green's function, the local spin susceptibility and the optical conductivity; along with the temperature dependence of the d.c. resistivity. The time reparameterization soft mode (equivalent to the boundary graviton in holographically dual models of two-dimensional quantum gravity) makes important contributions to all observables, and provides a linear-in-temperature contribution to the d.c. resistivity.
