发表机构
University of Fribourg; University of Hamburg; Rice University; Stony Brook University; TU Wien（弗里堡大学; 汉堡大学; 莱斯大学; 石溪大学; 维也纳工业大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
开发基于非平衡稳态格林函数的非微扰方法，研究强场下非线性霍尔效应，超越恒定弛豫时间近似，揭示相互作用和电子-声子自能对霍尔信号的显著影响。
AI 中文摘要
量子材料中的非线性霍尔效应引起了广泛兴趣，然而现有研究大多关注弱场微扰区域。本文基于直流场驱动晶格系统的非平衡稳态格林函数，发展了一种非微扰方法，通过自能引入耗散和相互作用，超越了恒定弛豫时间近似，并同时处理带间和带内跃迁。应用于双带半金属模型，我们的方法直接获得了非微扰交叉区域（非平衡分布边缘达到贝里曲率热点）之外的强场霍尔响应，而恒定弛豫时间估计和贝里曲率偶极子计算在此区域变得不可靠。我们进一步证明，动力学平均场理论中的相互作用和电子-声子自能可以显著改变霍尔信号。我们的框架能够定量模拟非平衡非线性霍尔现象，并为强场输运实验提供指导。
英文摘要
The nonlinear Hall effect in quantum materials has attracted broad interest, yet most existing studies focus on the weak-field, perturbative regime. Here we develop a nonperturbative approach based on nonequilibrium steady-state Green's functions for dc-field-driven lattice systems, with dissipation and interactions incorporated through self-energies beyond the constant relaxation-time approximation and interband transitions treated alongside their intraband counterparts. Applied to a two-band semimetal model, our approach provides direct access to the strong-field Hall response beyond the nonperturbative crossover where the edge of the nonequilibrium distribution reaches Berry-curvature hot spots, a regime in which constant relaxation-time estimates and Berry curvature dipole calculations become unreliable. We further demonstrate that interaction and electron-phonon self-energies within dynamical mean-field theory can substantially change the Hall signal. Our framework enables quantitative simulations of nonequilibrium nonlinear Hall phenomena and provides guidance for strong-field transport experiments.
