我們以YBa2Cu3Oy 薄膜為實驗樣品,由量測其磁化率及磁滯曲線的結果得
知Tc約90K. 為了了解磁鬆弛與角度之關係,我們固定外加磁場為5000高
斯,夾角由0度至90度.測量磁化率隨時間的變化.利用Anderson-Kim模型,
次方律關係及渦流玻璃模型來分析實驗結果.藉由角度等於90度的數據,得
知三個模型在時間大於等於600秒後均可得一致的kT/Up,其值約
0.0073.利用以上之分析方式,觀察其他角度之磁鬆弛行為,顯示在高角度
的磁鬆弛速率小於低角度的磁鬆弛速率.

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.
We take YBCO thin film as experimental sample. By measuring the