论文标题
超导振幅和相位的微观自由能功能:无序超导体中的超流体密度
Microscopic free energy functional of superconductive amplitude and phase: Superfluid density in disordered superconductors
论文作者
论文摘要
对无序超导体的最新实验发现,超流体密度$ n_s(t)$ y且特征在于无序的特征,与平均顺序参数场或bcs的预期不同,仅幅度,仅振幅,图像超导体的图片。我们在这里描述了一种新的微观自由能功能,该功能明确描述了其对超导顺序的幅度和相位的依赖,并以量规不变的方式。我们在此处使用它在(静态)障碍存在下的非相互作用相位波动(高斯或谐波近似)的近似值中以获得$ n_s(t)$。我们将结果成功地与实验进行了比较。
Recent experiments on disordered superconductors find that the superfluid density $n_s(T)$ decreases dramatically and characteristically with disorder, differently from what is expected for a mean order parameter field or BCS, amplitude only, picture for the superconductor. We describe here a new microscopic free energy functional which explicitly describes its dependence on both the amplitude and phase of superconducting order, in a gauge invariant manner. We use this here in an approximation of noninteracting phase fluctuations (Gaussian or harmonic approximation) to obtain $n_s(T)$ in the presence of (static) disorder. We compare our results successfully with experiment.