YBa_2Cu_3O_(7-δ)超导体的磁穿透深度及相对能隙

MAGNETIC PENETRATION DEPTH AND REDUCED ENERGY GAP OF HIGH T_c SUPERCONDUCTORS YBa_2Cu_3O_(7-δ)

根据测得的表面电阻R_S(T),通过在BCS理论框架中引入一个修正电导率,计算出YBa_2Cu_3O_(7-δ)(YBCO)超导材料的磁穿透深度和简约能隙与温度的相关性.引入修正电导率主要是根据YBCO超导体中电子结构表示Cu-O链对微波表面电阻的贡献.计算得到的磁穿透深度和相对能隙与实验结果符合得相当好.

The temperature dependent magnetic penetration depth and the reduced energygap have been calculated from the measured R_s(T) of YBa_2Cu_3O_(7-δ)(YBCO) materials inthe frame work of BCS theory by introducing a modified conductivity, which is mainlybased on the electronic structure of YBCO superconductors to express the contribution ofCu-O chain to the microwave surface resistance. The calculated results for magnetic pene-tration depth and the reduced energy gap agree very well with the experimental data.