Theory of Local Density of States of d x2- y2-Wave Superconducting State Near the Surfaces of the t- J Model
Theory of Local Density of States of d x2- y2-Wave Superconducting State Near the Surfaces of the t- J Model
复制标题
t-J模型表面附近d x2- y2波超导态局域密度理论
DOI：
10.1143/jpsj.67.1118
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发表时间：
1998
影响因子：
1.7
通讯作者：
S. Kashiwaya
中科院分区：
文献类型：
--
作者：
Y. Tanuma;Y. Tanaka;M. Ogata;S. Kashiwaya
从理论上研究了d x 2 - y 2 波超导体表面附近的电对势和局域态密度的空间依赖性。该计算基于具有 Gutzwiller 近似的平均场理论中的 t - J 模型。考虑了各种类型的表面几何形状。与我们在扩展哈伯德模型中的结果类似，我们发现零能态的形成强烈依赖于表面几何形状。除了这个特征之外，当超交换相互作用 J 很大时，零能态会产生 (110) 表面的峰值分裂。这是由于表面附近感应的横波分量造成的。目前的结果解释了高温超导体表面自发时间反转对称性破缺的微观起源。
Spatial dependencies of the pair potential and the local density of states near the surfaces of d x 2 - y 2 -wave superconductors are studied theoretically. The calculation is based on the t - J model within a mean-field theory with Gutzwiller approximation. Various types of surface geometries are considered. Similar to our result in the extended Hubbard model, it is found that the formation of zero-energy states strongly depends on the surface geometry. In addition to this feature, the zero-energy states give peak splitting for the (110) surfaces when the super-exchange interaction J is large. This is due to the induced s -wave component near the surface. The present result explains the microscopic origin of the spontaneous time-reversal symmetry breaking at the surfaces of high- T c superconductors.