摘要
本文用并联约瑟夫逊结模型讨论了在加场情况下（H：0－200Oc），Y1B2C3O7-δ块材样品的临界电流随外磁场的变化关系。得到的Ic(H)－H关系与实验结果能很好地吻合，根据该模型，可得到一个标志材料性能的参量H0（10－10^2Oc）它是Ic（H）随H急剧下降段所对应的场，H0越大，Ic随H变化越缓慢，同时，由该模型可以看到提高各约瑟夫逊结的ic(o)，减小晶粒穿透深度，减小晶粒尺寸和晶界相厚度，有利于提高材料的临界电流密度。
The relationships between the critical current of Y_1Ba_2Cu_3O_(7-δ) bulk samples and the applied field as the field increased were calculated with the model of parallel Josephson junctions. The results of measurement arc correspondent with the experimental results. The model gives an important parameter H_0 (about 10～10~2O_e) . The i_c (H) sharply reduces as the field increases when H<H_0.It is helpful for improving the properties of the samples by increasing the i_c (O) of each Josephson junction, and decreasing the Penetration depth , the size of grains and also the distance between grains.
