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arXiv · 0708.3024

Pump-Probe Experiments on the Single-Molecule Magnet Fe8 : Measurement of Excited Level Lifetimes

S. Bahr·K. Petukhov·V. Mosser·W. Wernsdorfer
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Abstract

We present magnetization measurements on the single molecule magnet Fe8 in the presence of pulsed microwave radiation. A pump-probe technique is used with two microwave pulses with frequencies of 107 GHz and 118 GHz and pulse lengths of several nanoseconds to study the spin dynamics via time-resolved magnetization measurements using a Hall probe magnetometer. We find evidence for short spin-phonon relaxation times of the order of one microsecond. The temperature dependence of the spin-phonon relaxation time in our experiments is in good agreement with previously published theoretical results. We also established the presence of very short energy diffusion times, that act on a timescale of about 70 ns.

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S. Bahr, K. Petukhov, V. Mosser, W. Wernsdorfer. 2007-08-22. Pump-Probe Experiments on the Single-Molecule Magnet Fe8 : Measurement of Excited Level Lifetimes. https://doi.org/10.1103/physrevlett.99.147205

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