Electronic structure and quantum criticality in Ba(Fe_1-x-y Co_xMn_y)₂As₂, an ARPES study

¹ Helmholtz - Zentrum Berlin - Albert-Einstein-Strasse 15, D-12489 Berlin, Germany, EU
² Karlsruhe Institute of Technology, Institut für Festkörperphysik - D-76021 Karlsruhe, Germany, EU
³ Leibniz - Institute for Solid State and Materials Research Dresden - P.O. Box 270116, D-01171 Dresden, Germany, EU
⁴ Fakultät für Physik, Universität Duisburg - Essen - Lotharstrasse 1, D-47048 Duisburg, Germany, EU
⁵ Technische Universität Berlin, Institut für Optik und Atomare Physik - Strasse des 17. Juni 136, D-10623 Berlin, Germany, EU
⁶ Institut für Experimentalphysik, Universität Hamburg - Luruper Chaussee 149, D-22761 Hamburg, Germany, EU
⁷ Center for Free - Electron Laser Science/DESY - Notkestrasse 85, D-22607 Hamburg, Germany, EU

Received: 24 June 2013
Accepted: 18 August 2013

Abstract

We used angle-resolved photoemission spectroscopy (ARPES) and density functional theory calculations to study the electronic structure of for and . From ARPES we derive that the substitution of Fe by Mn does not lead to hole doping, indicating a localization of the induced holes. An evaluation of the measured spectral function does not indicate a diverging effective mass or scattering rate near optimal doping. Thus, the present ARPES results indicate a continuous evolution of the quasiparticle interaction and therefore question previous quantum critical scenarios.