标题： 掺杂诱导的铜氧化物中三维电荷有序的稳定化 显示英文标题

标题： Dopant-induced stabilization of three-dimensional charge order in cuprates

摘要： 我们研究了Pr掺杂在YBa$_2$Cu$_3$O$_7$ (YBCO7)中稳定三维(3D)电荷序的微观机制。 密度泛函理论计算确定了Ba位和Y位取代的最低能量Pr超晶格。 在Ba位情况下，较小的Pr离子将周围的原子拉向内部。 这种呼吸模式畸变将电荷条纹壁固定到Pr柱，并迫使它们沿$c$轴对齐。 Y位的Pr比宿主离子更大，产生向外的畸变，并无法固定条纹。 粗粒度蒙特卡罗模拟显示，条纹相关长度随着Pr掺杂剂的结构相关长度增加，这与先前实验中的观察结果一致。 因此，我们将掺杂剂诱导的晶格钉扎确定为Pr掺杂YBCO7中3D电荷序的关键机制。 这种方法为通过有针对性的离子取代工程电子序提供了定量指导。 显示英文摘要

摘要： We investigate the microscopic mechanisms behind the stabilization of three-dimensional (3D) charge order by Pr doping in YBa$_2$Cu$_3$O$_7$ (YBCO7). Density-functional-theory calculations locate the lowest-energy Pr superlattices for both Ba- and Y-site substitution. In the Ba-site case, the smaller Pr ion pulls the surrounding atoms inward. This breathing-mode distortion pins charge-stripe walls to the Pr columns and forces them to align along the $c$ axis. Y-site Pr is larger than the host ion, produces an outward distortion, and fails to pin the stripes. Coarse-grained Monte-Carlo simulations show that the stripe correlation length rises in step with the structural correlation length of the Pr dopant as observed in prior experiments. We thus identify dopant-induced lattice pinning as the key mechanism behind 3D charge order in Pr-doped YBCO7. This approach provides quantitative guidelines for engineering electronic orders through targeted ionic substitution.