Common Electronic Features and Electronic Nematicity in Parent Compounds of Iron-Based Superconducto

• 作 者: 刘德发 赵林 何少龙 胡勇 沈兵 黄建伟 梁爱基 徐煜 刘旭 何俊峰 牟代翔 刘单于 刘海云 刘国东 张文号 李坊森 马旭村 薛其坤 陈仙辉 陈根富 俞理 张君 许祖彦 陈创天 周兴江
• 机 构: National Laboratory for Superconductivity,Beijing National Laboratory for Condensed Matter Physics,I
• 出 处: Chinese Physics Letters
• 发表日期: 2016年07期
• 关键词: Brillouin corners nematic bands parent Angle dominated Fermi splitting momentum

We report comprehensive angle-resolved photoemission investigations on the electronic structures and nematicity of the parent compounds of the iron-based superconductors including CeFeAsO,BaFe_2As_2,NaFeAs,FeSe and undoped FeSe/SrTiO_3 films with 1,2 and 20 layers.While the electronic structure near the Brillouin zone center Γ varies dramatically among different materials,the electronic structure near the Brillouin zone corners(M points),as well as their temperature dependence,are rather similar.The electronic structure near the zone corners is dominated by the electronic nematicity that gives rise to a band splitting of the d_(xz) and d_(yz) bands below the nematic transition temperature.A clear relation is observed between the band splitting magnitude and the onset temperature of nematicity.Our results may shed light on the origin of nematicity,its effect on the electronic structures,and its relation with superconductivity in the iron-based superconductors.

We report a comprehensive angle-resolved photoemission investigations on the electronic structures and nematicity of the parent compounds of the iron-based superconductors including CeFeAsO, BaFe 2 As 2, NaFeAs, FeSe and undoped FeSe / SrTiO 3 films with 1, 2 and 20 layers. Whilst the electronic structure near the Brillouin zone center Γquentى among other materials, the electronic structure near the Brillouin zone corners (M points), as well as their temperature dependence, are rather similar. The electronic structure near the zone corners is dominated by the electronic nematicity that gives rise to a band splitting of the d_ (xz) and d_ (yz) bands below the nematic transition temperature. A clear relation is observed between the band splitting magnitude and the onset temperature of nematicity. These results may shed light on the origin of nematicity, its effect on the electronic structures, and its relation with superconductivity in the iron-based superconductors.