标题： 超导CuxTiSe2中的亚稳短程电荷有序态 显示英文标题

标题： Metastable short-range charge order in superconducting CuxTiSe2

摘要： 在包括铜氧化物、过渡金属二硫属化物（TMDs）以及稀土三碲化物在内的多种材料中，在短程电荷密度波（CDW）有序态附近发现了超导性。 当引入淬火无序时，通常会发生从长程到短程电荷有序的转变，但目前尚不清楚这种无序如何破坏CDW。 在这里，我们使用X射线光子关联光谱（XPCS），研究了典型的TMD超导体CuxTiSe2，并表明无序诱导了显著的CDW动力学。 我们在名义转变温度以上观测到CDW相位波动的时间尺度为分钟到小时，同时秩序参数幅度保持有限。 这些长时间尺度的波动阻止了系统在冷却过程中找到全局自由能最小值，最终将其困在一个短程有序的亚稳态中。 我们的研究结果展示了相关无序如何引发一种可能有利于超导出现的独特畴形成机制。 显示英文摘要

摘要： In a vast array of materials, including cuprates, transition metal dichalcogenides (TMDs) and rare earth tritellurides, superconductivity is found in the vicinity of short-range charge density wave (CDW) order. The crossover from long-range to short-range charge order often occurs as quenched disorder is introduced, yet it is unclear how this disorder disrupts the CDW. Here, using x-ray photon correlation spectroscopy (XPCS), we investigate the prototypical TMD superconductor CuxTiSe2 and show that disorder induces substantial CDW dynamics. We observed the CDW phase fluctuation on a timescale of minutes to hours above the nominal transition temperature while the order parameter amplitude remains finite. These long timescale fluctuations prevent the system from finding the global free energy minimum upon cooling and ultimately traps it in a short-range ordered metastable state. Our findings demonstrate how correlated disorder can give rise to a distinct mechanism of domain formation that may be advantageous to the emergence of superconductivity.