Temperature dependence of antiferromagnetic susceptibility in ferritin

Autor: Silva, N. J. O., Millan, A., Palacio, F., Kampert, E., Zeitler, U., Rakoto, H., Amaral, V. S.
Rok vydání: 2009
Předmět:
Druh dokumentu: Working Paper
DOI: 10.1103/PhysRevB.79.104405
Popis: We show that antiferromagnetic susceptibility in ferritin increases with temperature between 4.2 K and 180 K (i. e. below the N\'{e}el temperature) when taken as the derivative of the magnetization at high fields ($30\times10^4$ Oe). This behavior contrasts with the decrease in temperature previously found, where the susceptibility was determined at lower fields ($5\times10^4$ Oe). At high fields (up to $50 \times10^4$ Oe) the temperature dependence of the antiferromagnetic susceptibility in ferritin nanoparticles approaches the normal behavior of bulk antiferromagnets and nanoparticles considering superantiferromagnetism, this latter leading to a better agreement at high field and low temperature. The contrast with the previous results is due to the insufficient field range used ($< 5 \times10^4$ Oe), not enough to saturate the ferritin uncompensated moment.
Comment: 7 pages, 7 figures, accepted in Phys. Rev. B
Databáze: arXiv