μ SR evidence of low frequency spin fluctuations in the AF phase of hole-doped NiO

F. Tedoldi; A. Campana; P. Carretta

doi:10.1007/s100510050607

EPJ

μ SR evidence of low frequency spin fluctuations in the AF phase of hole-doped NiO

F. Tedoldi, A. Campana and P. Carretta

INFM-Department of Physics "A. Volta", University of Pavia, 27100 Pavia, Italy

Received: 27 April 1998
Accepted: 21 August 1998
Published online: 15 January 1999

Abstract

μSR measurements in the antiferromagnetic (AF) phase of Ni1-xLi_xO for 0≤x≤0.10 are reported. While in pure NiO the muon longitudinal depolarization rate

is found almost temperature independent, in the Li-doped compounds broad maxima around 130 K are observed. These maxima are associated with the progressive freezing of the spin fluctuations of S=1/2 defects induced by the localization of the extra-holes. From the temperature dependence of

and the stretched exponential form of the depolarization, insights on the distribution of correlation times for the fluctuating field at the muon site are derived.

PACS: 75.30.Hx – Magnetic impurity interactions / 75.40.Gb – Dynamic properties (dynamic susceptibility, spin waves, spin diffusion, dynamic scaling, etc.) / 76.75.+i – Muon spin rotation and relaxation