标题： 筛选和有效RPA类似电荷磁化率在扩展哈伯德模型中 显示英文标题

标题： Screening and effective RPA-like charge susceptibility in the extended Hubbard model

摘要： 我们将最近引入的单玻色子交换形式化方法推广到非局域相互作用。 在二维扩展Hubbard模型的函数重整化群应用中，我们表明，在中等相互作用强度下，剩余函数的流可以忽略。 通过进行涨落诊断，我们在各种参数区域中探讨了局域和最近邻相互作用之间的相互作用所产生的物理现象。 与磁性和超导磁化率不同，电荷磁化率似乎由随机相位近似（RPA）描述。 我们表明，这种行为可以追溯到密度费米子-玻色子耦合的重整化中的抵消作用。 显示英文摘要

摘要： We generalize the recently introduced single-boson exchange formalism to nonlocal interactions. In the functional renormalization group application to the extended Hubbard model in two dimensions, we show that the flow of the rest function can be neglected up to moderate interaction strengths. We explore the physics arising from the interplay between onsite and nearest-neighbor interactions in various parameter regimes by performing a fluctuation diagnostics. Differently from the magnetic and superconducting susceptibilities, the charge susceptibility appears to be described by the random phase approximation (RPA). We show that this behavior can be traced back to cancellations in the renormalization of the density fermion-boson coupling.