摘要
铜氧化物高温超导体的超导机理是近30年来凝聚态物理研究领域的一个重大科学难题.赝能隙和d波配对对称性是对铜氧化物超导体研究所得出的重要实验观察.然而,过去的宏观测量描述的是超导层和电荷库层性质叠加的结果;而微观表面探测主要在实验上易获得的电荷库层进行,无法保证其测量结果能真实表征夹在电荷库层之间的超导结构单元(CuO_2).因此,获得铜氧化物高温超导体的超导层CuO_2且对其进行直接测量是非常必要的,对揭示其高温超导机理具有重要的科学意义.本文综述最近五年内对铜氧化物中CuO_2层相关的扫描隧道显微镜研究结果,对铜氧化物中赝能隙及其与超导电性的关系进行讨论.这些研究为理解高温超导机理提供了重要的思路.
The nature of high temperature superconductivity in cuprates has currently been one of major scientific problems in condensed matter physics. In cuprate superconductors, the d-wave pairing symmetry with gap nodes on the Fermi surface and the pseudogap phenomenology have been well documented and regarded as the most important findings in the 30-year study. Due to the very complicated layered structure of cuprates, which consist of alternative superconducting（copper oxide） and non-superconducting（charge reservoir） layers, almost all macroscopic experiments previously performed probe the combined properties of both superconducting layers and non-superconducting layers. Meanwhile,surface-sensitive techniques, including scanning tunneling microscopy and spectroscopy, have mostly conducted on the cleaved reservoir layers, while the copper oxide layer is usually sandwiched between the reservoir layers. Because copper oxide layers are the main building blocks of cuprates, a direct probe of the copper oxide layer should be most desirable,although it is highly challenging experimentally. However, the significant progress has been made in the recent years. In this article we review the recent efforts on the preparation and direct observation of copper oxide layers in cuprates, and shed insight on the relationship between the pseudogap and superconductivity. These results might open new avenue for building up new high temperature superconductors and understanding the pairing mechanism of high temperature superconductivity in cuprates.
作者
窦子媛
吕衍凤
宋灿立
马旭村
薛其坤
DOU ZiYuan;LV YanFeng;SONG CanLi;MA XuCun;XUE QiKun(State Key Laboratory of Low-Dimensional Quantum Physics,Department of Physics,Tsinghua University,Beijing 100084,China)
出处
《中国科学：物理学、力学、天文学》
CSCD
北大核心
2018年第8期36-50,共15页
Scientia Sinica Physica,Mechanica & Astronomica
基金
国家自然科学基金(编号:11634007
21573121)
国家重点基础研究发展计划(编号:2015CB921001)资助
关键词
铜氧化物超导电性
铜氧面
超导能隙
扫描隧道显微谱
cuprate superconductors
copper oxide
superconducting gap
scanning tunneling microscopy
