We present a study of the magnetic properties of the superparamagnetic ferritin system by employing zero-field (ZF) and longitudinal-field (LF) μ+SR measurements. Two μ+ fractions with different depolarisation behaviour are detected, one arising from muons stopped in the organic shell and one from muons stopped in the mineral core. The freezing of the superparamagnetic moments is evident in the temperature evolution of the ZF relaxation rates of both fractions. It occurs gradually below ≈ 60 K and is essentially complete at ≈ 11 K. The results are consistent with a distribution of blocking temperatures which in turn reflects the distribution of core sizes.
|Number of pages||6|
|Publication status||Published - 1997 Dec 1|
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Nuclear and High Energy Physics
- Condensed Matter Physics
- Physical and Theoretical Chemistry