【摘要】 采用两带Richardson模型,用随机矩阵理论方法研究了具有高斯能级分布的金属小颗粒的超导电性,计算了系统的熵、比热跃变和超导临界磁场.结果表明,带间相互作用有利于系统的超导电性,带间相互作用越强,超导临界温度越高,超导临界尺寸越小.大的基态自旋S不利于系统的超导电性,基态自旋S越大,超导临界温度越低,超导临界尺寸越大.对于S≠0的自旋基态,随着颗粒尺寸的减小只存在超导衰减现象,而对于S=0的自旋基态,则先出现超导增强现象,随后出现超导衰减现象.理论结果与实验符合.更多还原

【Abstract】 Based on two-band Richardson model,by random matrix method we have studied the superconductivity of small metallic particle with Gaussian energy level distribution.Entropy,specific heat jump and critical magnetic field of the system have been calculated.The obtained results show that the interband interaction is favorable for the superconductivity of the system,with the increasing of the interband interaction the superconducting critical temperature increases,and the superconducting critical dimension decreases.Large ground-state spin Sis unfavorable for the superconductivity of the system, the superconducting critical temperature decreases, and the superconducting critical dimension increases with the increasing of the ground-state spin.For S ≠ 0,with the decrease of metal particle dimension only superconducting attenuation phenomenon appears.But for S = 0,the superconducting enhancement phenomenon appears first,and then the superconducting attenuation phenomenon appears.Our results are in agreement with experiments.更多还原