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arXiv · 0706.3506

Experimental Estimates of Dephasing Time in Molecular Magnets

Amit Keren·Oren Shafir·Efrat Shimshoni·Valerie Marvaud·Anne Bachschmidt·Jerome Long
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Abstract

Muon spin relaxation measurements in isotropic molecular magnets (MM) with a spin value S ranging from 7/2 to 27/2 are used to determine the magnitude and origin of dephasing time $τ_ϕ$ of molecular magnets. It is found that $τ_ϕ$ ~ 10 nsec with no S or ligand dependence. This indicates a nuclear origin for the stochastic field. Since $τ_ϕ$ is a property of the environment, we argue that it is a number common to similar types of MM. Therefore, $τ_ϕ$ is shorter than the Zener and tunneling times of anisotropic MM such as Fe8 or Mn4 for standard laboratory sweep rates. Our findings call for a stochastic Landau-Zener theory in this particular case.

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Amit Keren, Oren Shafir, Efrat Shimshoni, Valerie Marvaud, Anne Bachschmidt, Jerome Long. 2007-06-26. Experimental Estimates of Dephasing Time in Molecular Magnets. https://doi.org/10.1103/physrevlett.98.257204

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