Neutron depolarization measurements of magnetite in chiton teeth

International Conference on Polarised Neutrons for Condensed Matter Investigations

Seifert, M.^1,2 ; Schulz, M.^1,2 ; Benka, G.^2 ; Pfleiderer, C.^2 ; Gilder, S.^3

Heinz Maier-Leibnitz Zentrum (MLZ), Technical University of Munich, Garching

D-85748, Germany^1

Physics Department, Technical University of Munich, Garching

D-85748, Germany^2

Department of Earth and Environmental Sciences, Ludwig-Maximilians-Universitat Munchen, Munich

D-80539, Germany^3

关键词: Comparative studies;    Magnetic minerals;    Magnetic remanence;    Natural sources;    Neutron depolarization;    Paleomagnetists;    Single-domain state;    Vibrating sample magnetometer;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/862/1/012024/pdf
DOI  :  10.1088/1742-6596/862/1/012024

来源: IOP

【 摘 要 】

Magnetite constitutes one of the most abundant magnetic minerals in the Earth's crust. In the single domain state, magnetite often carries the magnetic remanence in rocks due to its stable and strong magnetic remanence. Hence it is of keen interest to paleomagnetists who study the ancient magnetic field preserved in the rock record. The extremely small size range and vulnerability to oxidation of single domain magnetite makes synthetization and preservation virtually impossible. Consequently, most experimental work on magnetite under pressure is carried out on multidomain magnetite. The radula of the marine mollusc chiton (Polyplacophora) is one of the few natural sources of single domain magnetite. We have performed a comparative study on samples of chiton radula in a vibrating sample magnetometer (VSM) and with the newly evolving neutron depolarization imaging (NDI) technique. Despite a constant offset between the VSM and NDI data in the coercivity we find a good agreement between the two techniques.