Conductance anomalies in a normal-metal-d-wave superconductor junction.
Conductance anomalies in a normal-metal-d-wave superconductor junction.
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普通金属 d 波超导结中的电导异常。
DOI：
10.1103/physrevb.53.3604
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Ting
中科院分区：
文献类型：
--
作者：
Xu;Miller;Ting
利用Bogoliubov{endash}de Gennes方程，研究了Andreev反射对正常金属与{itald}{sub{italxy}}波超导体或具有{L_brace}110{r_brace}取向的{itald}{sub{italx}{sup2}{减去}{italy}{sup2}}波超导体之间结的电流-电压特性和微分电导的影响。我们的研究阐明了d波序参数符号变化的几个重要结果。特别是，当正常金属与d波超导体的界面处存在绝缘势垒时，获得了零偏压电导峰，这与在铜酸盐超导体上进行的大量实验是一致的。如果假设绝缘势垒位于正常金属中，则可以预测离超导体表面几个相干长度，能隙内的束缚态，以及随后的微分电导中的亚能隙共振。这些共振的位置与各向同性或各向异性的S}波超导体的预测位置是异相的，因此提供了独特的对态对称性特征。{版权所有}{1996年美国物理学会。}
The effects of Andreev reflection on the current-voltage characteristic and differential conductance of a junction between a normal metal and a {ital d}{sub {ital xy}}-wave superconductor, or equivalently, a {ital d}{sub {ital x}{sup 2}{minus}{ital y}{sup 2}}-wave superconductor with a {l_brace}110{r_brace}-oriented surface are investigated using the Bogoliubov{endash}de Gennes equations. Our study elucidates several important consequences of the sign change of a {ital d}-wave order parameter. In particular, a zero-bias conductance peak is obtained when an insulating barrier exists at the interface between the normal metal and the {ital d}-wave superconductor, consistent with numerous experiments performed on cuprate superconductors. If the insulating barrier is assumed to reside in the normal metal, several coherence lengths away from the superconductor surface, bound states within the energy gap, and consequent subgap resonances in the differential conductance, are predicted. The positions of these resonances are out of phase with respect to those predicted for an isotropic or anisotropic {ital s}-wave superconductor, thus providing unique signatures of pairing state symmetry. {copyright} {ital 1996 The American Physical Society.}