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تسجيل مستخدم جديدObservation of the distribution of molecular spin states by resonant quantum tunneling of the magnetization
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Below 360 mK, Fe magnetic molecular clusters are in the pure quantum relaxation regime and we show that the predicted square-root time relaxation is obeyed, allowing us to develop a new method for watching the evolution of the distribution of molecular spin states in the sample. We measure as a function of applied field H the statistical distribution P(xi_H) of magnetic energy bias xi_H$ acting on the molecules. Tunneling initially causes rapid transitions of molecules, thereby digging a hole in P(xi_H) (around the resonant condition xi_H = 0). For small initial magnetization values, the hole width shows an intrinsic broadening which may be due to nuclear spins.
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