Superconductivity from buckled-honeycomb-vacancy ordering  

一种新型超导母体:褶皱的蜂窝状空位有序

作　　者：Yanpeng Qi Tianping Ying Xianxin Wu Zhuoya Dong Masato Sasase Qing Zhang Weiyan Liu Masaki Ichihara Yanhang Ma Jiangping Hu Hideo Hosono 齐彦鹏;应天平;吴贤新;董卓雅;Masato Sasase;张青;刘为燕;Masaki Ichihara;马延航;胡江平;Hideo Hosono(School of Physical Science and Technology,ShanghaiTech University,Shanghai 201210,China;Materials Research Center for Element Strategy,Tokyo Institute o f Technology,Yokohama 226-8503,Japan;Institut fur Theoretische Physik und Astrophysik,Julius-Maximilians-Universitat Wurzburg,Wurzburg 97074,Germany;Beijing National Laboratory for Condensed Matter Physics and Institute of Physics,Chinese Academy of Sciences.Beijing 100190,China)

机构地区：[1]School of Physical Science and Technology,ShanghaiTech University,Shanghai 201210,China [2]Materials Research Center for Element Strategy,Tokyo Institute o f Technology,Yokohama 226-8503,Japan [3]Institut fur Theoretische Physik und Astrophysik,Julius-Maximilians-Universitat Wurzburg,Wurzburg 97074,Germany [4]Beijing National Laboratory for Condensed Matter Physics and Institute of Physics,Chinese Academy of Sciences.Beijing 100190,China

出　　处：《Science Bulletin》2021年第4期327-331,M0003,共6页科学通报（英文版）

基　　金：support by the National Key Research and Development Program of China(2018YFA0704300);the National Natural Science Foundation of China(U1932217 and 11974246);the Natural Science Foundation of Shanghai(19ZR1477300);supported by MEXT Element Strategy Initiative to form Core Research Center;partially supported by ChEM,SPST of ShanghaiTech University(02161943);Analytical Instrumentation Center(SPST-AIC10112914),SPST of ShanghaiTech University;supported by the National Natural Science Foundation of China(11888101)。

摘　　要：Vacancies are prevalent and versatile in solid-state physics and materials science.The role of vacancies in strongly correlated materials,however,remains uncultivated until now.Here,we report the discovery of an unprecedented vacancy state forming an extended buckled-honeycomb-vacancy(BHV)ordering in Ir16Sb18.Superconductivity emerges by suppressing the BHV ordering through squeezing of extra Ir atoms into the vacancies or isovalent Rh substitution.The phase diagram on vacancy ordering reveals the superconductivity competes with the BHV ordering.Further theoretical calculations suggest that this ordering originates from a synergistic effect of the vacancy formation energy and Fermi surface nesting with a wave vector of(1/3,1/3,0).The buckled structure breaks the crystal inversion symmetry and can mostly suppress the density of states near the Fermi level.The peculiarities of BHV ordering highlight the importance of"correlated vacancies"and may serve as a paradigm for exploring other non-trivial excitations and quantum criticality.空位在材料体系中无处不在,空位的存在也极大地影响了材料的光学、热学、电学等性质.目前,空位的研究主要集中在弱关联的体系,而在强关联体系中的空位以及空位和其他新奇量子现象的关系则知之甚少.本文在强关联铱化物Ir16Sb18中发现了一种新奇的空位有序:褶皱的蜂窝状空位序.理论计算表明实空间的空位有序来源于倒空间的费米面嵌套,而空位有序的形成破坏了对称性,使得费米面附近的电子局域化.通过在空位中引入Ir或者用Rh来替代Ir,可以有效地破坏空位有序从而引入超导电性.空位有序与超导电性的竞争关系表明:具有褶皱的蜂窝状空位有序的Ir16Sb18是一种新型的超导母体.这种独特的褶皱蜂窝状空位有序,及其实空间-倒空间的关系,表明了"关联空位"的重要性,这为探索更多新奇量子临界现象带来契机.

关 键 词：SUPERCONDUCTIVITY VACANCIES Iridates Phase diagram 

分 类 号：TB383.4[一般工业技术—材料科学与工程]