Guyard W, Sacuto A, Cazayous M, Gallais Y, Le Tacon M, Colson D, Forget A
Laboratoire Matériaux et Phénomnes Quantiques (UMR 7162 CNRS), Université Paris Diderot-Paris 7, Bat. Condorcet, 10 rue Alice Domon et Léonie Duquet, 75205 Paris CEDEX 13, France.
Phys Rev Lett. 2008 Aug 29;101(9):097003. doi: 10.1103/PhysRevLett.101.097003. Epub 2008 Aug 27.
Although more than 20 years have passed, the identification of the superconducting order parameter in cuprates is still under debate. Here, we show that the gap size near the nodes is a good candidate for the order parameter: it scales with the critical temperature Tc over a wide doping range and displays a significant temperature dependence below Tc in both the underdoped and the overdoped regimes. In contrast, the gap size at the antinodes does not scale with Tc in the underdoped regime and appears to be controlled by the pseudogap which persists below Tc.
尽管已经过去了20多年，但铜酸盐中超导序参量的识别仍在争论之中。在此，我们表明节点附近的能隙大小是序参量的一个很好候选者：在很宽的掺杂范围内，它与临界温度Tc成比例，并且在欠掺杂和过掺杂区域中，在Tc以下都表现出显著的温度依赖性。相比之下，在欠掺杂区域中，反节点处的能隙大小并不与Tc成比例，并且似乎由在Tc以下持续存在的赝能隙所控制。
