• Ricci, A.; Poccia, N.; Campi, G.; Mishra, S.; Müller, L.; Joseph, B.; Shi, B.; Zozulya, A.; Buchholz, M.; Trabant, C.; Lee, J.C.T.; Viefhaus, J.; Goedkoop, J.B.; Nugroho, A.A.; Braden, M.; Roy, S.; Sprung, M.; Schüßler-Langeheine, C.: Measurement of Spin Dynamics in a Layered Nickelate Using X-Ray Photon Correlation Spectroscopy: Evidence for Intrinsic Destabilization of Incommensurate Stripes at Low Temperatures. Physical Review Letters 127 (2021), p. 057001/1-7

10.1103/physrevlett.127.057001
Open Access Version

Abstract:
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.