We study the temporal stability of stripe-type spin order in a layered nickelate with x-ray photon correlation spectroscopy and observe fluctuations on timescales of tens of minutes over a wide temperature range. These fluctuations show an anomalous temperature dependence: they slow down at intermediate temperatures and speed up on both heating and cooling. This behavior appears to be directly connected with spatial correlations: stripes fluctuate slowly when stripe correlation lengths are large and become faster when spatial correlations decrease. A low-temperature decay of nickelate stripe correlations, reminiscent of what occurs in cuprates as a result of a competition between stripes and superconductivity, hence occurs via loss of both spatial and temporal correlations.

中文翻译：

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使用 X 射线光子相关光谱法测量层状镍酸盐中的自旋动力学：低温下不相称条纹的内在不稳定的证据

我们使用 X 射线光子相关光谱研究了层状镍酸盐中条纹型自旋顺序的时间稳定性，并在很宽的温度范围内观察了数十分钟时间尺度上的波动。这些波动显示出异常的温度依赖性：它们在中间温度下减慢，而在加热和冷却时加速。这种行为似乎与空间相关性直接相关：当条带相关长度较大时，条带波动缓慢，而当空间相关性降低时，波动会更快。镍酸盐条纹相关性的低温衰减，让人想起由于条纹和超导性之间的竞争而在铜酸盐中发生的情况，因此通过空间和时间相关性的丧失而发生。