论文标题
零场表面电荷由于$ d $ - 波超导体的差距抑制而导致
Zero-Field Surface Charge Due to the Gap Suppression in $d$-Wave Superconductors
论文作者
论文摘要
我们对沿[110]方向切开的型号$ d $波超导体的表面附近的电荷的重新分布进行了微观研究，使用增强的准经典方程，其费米表面适用于库层超导体。我们确定了两种可能的机制，即带电颗粒与众所周知的磁性霍尔效应不同的机制。这对电位梯度（PPG）力是由于对配对电位的表面影响以及正常状态（SDOS）在FERMI水平上的状态密度（SDOS）斜率引起的正常和超导区域之间的压力差。我们目前的结果表明，尽管没有超电流，但在表面周围诱导了电荷。此外，由于所有逼真的电子填充$ n = 0.8 $，$ 0.9 $和$ 1.15 $，由于SDOS压力引起的充电效应在ppg力量上占主导地位。此外，对于填充$ n = 1.15 $，PPG力和SDOS压力贡献具有相同的负符号，这给出了更大的总表面电荷，即表面电荷的符号和量都在很大程度上取决于费米 - 表面曲率。我们还计算了增强的准经典理论中状态（LDOS）的局部密度。 LDO中出现在空间上变化的局部颗粒不对称性，这表明存在电荷。
We perform a microscopic study on the redistribution of electric charge near the surface of a model $d$-wave superconductor cut along the [110] direction, with a Fermi surface appropriate for cuprate superconductors, using the augmented quasiclassical equations. We identify two possible mechanisms for the redistribution of charged particles different from the well-known magnetic Hall effect, namely; the pair potential gradient (PPG) force due to surface effects on the pair potential and the pressure difference between the normal and superconducting regions arising from the slope of the density of states (SDOS) in the normal states at the Fermi level. Our present results show that in spite of the absence of supercurrents, electric charge is induced around the surface. Moreover, the charging effect due to the SDOS pressure dominates over that due to the PPG force for all the realistic electron-fillings $n=0.8$, $0.9$, and $1.15$, at all temperatures. In addition, for the filling $n=1.15$, the PPG force and the SDOS pressure contributions have the same negative signs, which gives a larger total surface charge i.e., both the sign and amount of the surface charge depends greatly on the Fermi-surface curvature. We have also calculated the local density of states (LDOS) within the augmented quasiclassical theory. Spatially varying local particle-hole asymmetry appears in the LDOS, which suggests the presence of electric charge.
