Department of Physics, Loughborough University, Loughborough LE11 3TU, UK.
J Phys Condens Matter. 2010 Oct 13;22(40):403202. doi: 10.1088/0953-8984/22/40/403202. Epub 2010 Sep 14.
There has been a huge theoretical and experimental push to try to illuminate the mechanism behind the high-temperature superconductivity of copper oxides. Cuprates are distinguishable from conventional metallic superconductors in originating from the doping of the parent charge-transfer insulators. The superconducting parts are weakly coupled two-dimensional doped layers held together by the parent lattice. Apart from their high-T(c) they have other characteristic features including the 'superconducting' gap (SG) which develops below the superconducting critical temperature and can be seen in extrinsic and intrinsic tunnelling experiments as well as using high-resolution angle-resolved photoemission (ARPES); there also exists another energy gap, the 'pseudogap' (PG), which is a large anomalous gap that exists well above T(c). We present a brief review of recent theories behind the pseudogap and discuss in detail one specific (polaronic) approach which explains the SG, PG and unusual tunnelling characteristics of cuprate superconductors.
在阐明铜氧化物高温超导背后的机制方面，已经进行了大量的理论和实验研究。与源自母体电荷转移绝缘体掺杂的传统金属超导体相比，铜酸盐具有独特的性质。超导部分是由母体晶格结合在一起的弱耦合二维掺杂层。除了高临界温度 T(c)之外，它们还具有其他特征，包括在超导临界温度以下发展的“超导能隙”(SG)，可以在外部和内部隧道实验以及使用高分辨率角分辨光发射(ARPES)中看到;还存在另一个能隙，即“赝隙”(PG)，它是一个存在于 T(c)以上的大异常能隙。我们对赝隙背后的最新理论进行了简要回顾，并详细讨论了一种特定的(极化子)方法，该方法解释了铜酸盐超导体的 SG、PG 和异常隧道特性。
