2025/11/26 by Kadono, Ryosuke
#FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci)
paper · doi:10.48550/arxiv.2511.21013
It is shown by numerical simulations of muon spin relaxation (μSR) spectra and analysis of these using the Kubo-Toyabe relaxation function Gz\rm KT(t) that the anomalous peak in the fluctuation rate ν\rm KT around a specific temperature T^* and associated decrease of the linewidth Δ\rm KT above T^*, often observed in the previous μSR studies on ion diffusion, originate from the sharp increase in the ion jump rate ν\rm i against that of the muon νμ with increasing temperature. This indicates that a more detailed reanalysis of the vintage data using the "extended" Kubo-Toyabe relaxation function Gz\rm EA(t) incorporating the jump motion of both ions and implanted muon (which was also used to simulate the μSR spectra) is useful for the proper evaluation of ν\rm i and νμ. Meanwhile, it also suggests that the μSR results showing no such anomaly convey little information on ion diffusion.