Anomalies in the Relaxation of Small Magnetic Particles at Very Low Temperatures
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چکیده
The magnetization relaxation rate of small γ−Fe2O3 particles dispersed in a silica matrix has been measured from 60 mK to 5 K. It shows a minimum around 150 mK, that can be discussed in terms of either thermal or quantum relaxation regime.
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تاریخ انتشار 1996