Experimental Investigation of the Electronic Structure of Ca0.83La0.17Fe2As2
HUANG Yao-Bo1, RICHARD Pierre1**, WANG Ji-Hui2, WANG Xiao-Ping1,3, SHI Xun1,3, XU Nan1, WU Zheng2, LI Ang2, YIN Jia-Xin1, QIAN Tian1, LV Bing2, CHU Ching-Wu2, PAN Shu-Heng2,1, SHI Ming3, DING Hong1**
1Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing 100190 2Texas Center for Superconductivity and Department of Physics, University of Houston, TX 77204-5002, USA 3Paul Scherrer Institut, Swiss Light Source, CH-5232 Villigen PSI, Switzerland
Abstract：We performed a combined angle-resolved photoemission spectroscopy and scanning tunneling microscopy study of the electronic structure of electron-doped Ca0.83La0.17Fe2As2. A surface reconstruction associated with the dimerization of As atoms is observed directly in the real space, as well as the consequent band folding in the momentum space. Besides this band folding effect, the Fermi surface topology of this material is similar to that reported previously for BaFe1.85Co0.15As2, with Γ-centered hole pockets quasi-nested to M-centered electron pockets by the antiferromagnetic wave vector. Although no superconducting gap is observed by ARPES possibly due to low superconducting volume fraction, a gap-like density of states depression of 7.7±2.9 meV is determined by scanning tunneling microscopy.
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2013, Vol. 30 
