Mitrano Matteo, Lee Sangjun, Husain Ali A, Delacretaz Luca, Zhu Minhui, de la Peña Munoz Gilberto, Sun Stella X-L, Joe Young Il, Reid Alexander H, Wandel Scott F, Coslovich Giacomo, Schlotter William, van Driel Tim, Schneeloch John, Gu G D, Hartnoll Sean, Goldenfeld Nigel, Abbamonte Peter
Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
Sci Adv. 2019 Aug 16;5(8):eaax3346. doi: 10.1126/sciadv.aax3346. eCollection 2019 Aug.
Charge order is universal among high- cuprates, but its relation to superconductivity is unclear. While static order competes with superconductivity, dynamic order may be favorable and even contribute to Cooper pairing. Using time-resolved resonant soft x-ray scattering at a free-electron laser, we show that the charge order in prototypical La Ba CuO exhibits transverse fluctuations at picosecond time scales. These sub-millielectron volt excitations propagate by Brownian-like diffusion and have an energy scale remarkably close to the superconducting . At sub-millielectron volt energy scales, the dynamics are governed by universal scaling laws defined by the propagation of topological defects. Our results show that charge order in La Ba CuO exhibits dynamics favorable to the in-plane superconducting tunneling and establish time-resolved x-rays as a means to study excitations at energy scales inaccessible to conventional scattering techniques.
电荷序在高温铜酸盐中普遍存在，但其与超导性的关系尚不清楚。虽然静态序与超导性相互竞争，但动态序可能是有利的，甚至有助于库珀对的形成。利用自由电子激光的时间分辨共振软X射线散射，我们表明典型的LaBaCuO中的电荷序在皮秒时间尺度上表现出横向涨落。这些亚毫电子伏特激发通过类似布朗运动的扩散进行传播，并且具有与超导能隙非常接近的能量尺度。在亚毫电子伏特能量尺度下，动力学由拓扑缺陷传播所定义的通用标度律支配。我们的结果表明，LaBaCuO中的电荷序表现出有利于面内超导隧穿的动力学特性，并确立了时间分辨X射线作为研究传统散射技术无法达到的能量尺度上的激发的一种手段。
