Summary: | 碩士 === 國立師範大學 === 物理研究所 === 82 === We take YBCO thin film as experimental sample. By measuring the
magnetization, we know the critical temperature of the sample
is about 90 K. In order to realize the relation between
magnetic relaxation and angle, we fix the external field as
5000 Gauss, change the angle from 0 degree to 90 degree, and
measure the magnetization variation with time. We analyze the
results by Anderson-Kim model, Power law, and Vortex-Glass
model. By the data of 90 degree, we know that after 600 seconds
,those three models lead to a similar kT/Up value, about 0.0073
. With the same method, we observe the magnetic relaxation of
other angles, and find that the relaxation rate in higher angle
is slower than that in lower angle.
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