Inhomogeneous Low Frequency Spin Dynamics in La_{1.65}Eu_{0.2}Sr_{0.15}CuO_4

TL;DR

This study uses NMR to reveal inhomogeneous, glassy spin dynamics in La_{1.65}Eu_{0.2}Sr_{0.15}CuO_4, showing slow electronic spin fluctuations with a distribution of activation energies.

Contribution

It demonstrates that inhomogeneous slowing of spin fluctuations is a common feature in doped lanthanum cuprates, providing new insights into their spin dynamics.

Findings

Low temperature peak in La spin lattice relaxation rate

Wipeout of Cu NMR intensity due to slow spin fluctuations

Presence of a distribution of activation energies in spin dynamics

Abstract

We report Cu and La nuclear magnetic resonance (NMR) measurements in the title compound that reveal an inhomogeneous glassy behavior of the spin dynamics. A low temperature peak in the La spin lattice relaxation rate and the ``wipeout'' of Cu intensity both arise from these slow electronic spin fluctuations that reveal a distribution of activation energies. Inhomogeneous slowing of spin fluctuations appears to be a general feature of doped lanthanum cuprate.