磁场中的超导金属小粒子

Small Superconducting Grains in Magnetic Fields

将平均场方法同无规矩阵理论结合用于研究外加磁场对不同自旋s基态金属小粒子超导电性的影响 .我们发现 ,超导电性仍然会随着粒子尺寸的减小而衰减 ;外加磁场的存在将会使得除s>0任何态产生超导增强效应 .而对s=0 。

We use the mean field theory and random matrices to study the influence of applied magnetic fields on superconductivity of small metallic grains in different spin s ground-states, and find that in existence of applied magnetic fields the superconductivity can be enhanced but finally attenuates for all s>0 spin-states as the granular size decreases. But for the state of s=0, the enhancement always exists even if no magnetic fields are imposed.