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Relaxation and Landau-Zener experiments down to 100 mK in ferritin

M. Duran·E. del Barco·J. M. Hernandez·J. Tejada
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Abstract

Temperature-independent magnetic viscosity in ferritin has been observed from 2 K down to 100 mK, proving that quantum tunneling plays the main role in these particles at low temperature. Magnetic relaxation has also been studied using the Landau-Zener method making the system crossing zero resonant field at different rates, alpha=dH/dt, ranging from 10^{-5} to 10^{-3} T/s, and at different temperatures, from 150 mK up to the blocking temperature. We propose a new Tln(Delta H_{eff}/tau_0 alpha) scaling law for the Landau-Zener probability in a system distributed in volumes, where Delta H_{eff} is the effective width of the zero field resonance.

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M. Duran, E. del Barco, J. M. Hernandez, J. Tejada. 2001-09-21. Relaxation and Landau-Zener experiments down to 100 mK in ferritin. https://doi.org/10.1103/physrevb.65.172401

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