Effect of different in-chain impurities on the magnetic properties of the spin chain compound SrCuO2 probed by NMR

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

  • Yannic Utz - , Professur für Physik der Quantenmaterialien, Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden (Autor:in)
  • Franziska Hammerath - , Professur für Festkörperphysik/Elektronische Eigenschaften, Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden (Autor:in)
  • Roberto Kraus - , Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden (Autor:in)
  • Tobias Ritschel - , Professur für Physik der Quantenmaterialien (Autor:in)
  • Jochen Geck - , Professur für Physik der Quantenmaterialien (Autor:in)
  • Liviu Hozoi - , Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden (Autor:in)
  • Jeroen Van Den Brink - , Professur für Festkörpertheorie (gB/IFW), Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden (Autor:in)
  • Ashwin Mohan - , Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden, Institute of Chemical Technology (Autor:in)
  • Christian Hess - , Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden (Autor:in)
  • Koushik Karmakar - , Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden, Indian Institute of Science Education and Research Pune (Autor:in)
  • Surjeet Singh - , Indian Institute of Science Education and Research Pune (Autor:in)
  • Dalila Bounoua - , Centre national de la recherche scientifique (CNRS) (Autor:in)
  • Romuald Saint-Martin - , Centre national de la recherche scientifique (CNRS) (Autor:in)
  • Loreynne Pinsard-Gaudart - , Centre national de la recherche scientifique (CNRS) (Autor:in)
  • Alexandre Revcolevschi - , Centre national de la recherche scientifique (CNRS) (Autor:in)
  • Bernd Büchner - , Professur für Experimentelle Festkörperphysik (gB/IFW), Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden (Autor:in)
  • Hans Joachim Grafe - , Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden (Autor:in)

Abstract

The S=1/2 Heisenberg spin chain compound SrCuO2 doped with different amounts of nickel (Ni), palladium (Pd), zinc (Zn), and cobalt (Co) has been studied by means of Cu nuclear magnetic resonance (NMR). Replacing only a few of the S=1/2 Cu ions with Ni, Pd, Zn, or Co has a major impact on the magnetic properties of the spin chain system. In the case of Ni, Pd, and Zn an unusual line broadening in the low temperature NMR spectra reveals the existence of an impurity-induced local alternating magnetization (LAM), while strongly decaying spin-lattice relaxation rates T1-1 towards low temperatures indicate the opening of spin gaps. A distribution of gap magnitudes is implied by a stretched spin-lattice relaxation and a variation of T1-1 within the broad resonance lines. These observations depend strongly on the impurity concentration and therefore can be understood using the model of finite segments of the spin 1/2 antiferromagnetic Heisenberg chain, i.e., pure chain segmentation due to S=0 impurities. This is surprising for Ni as it was previously assumed to be a magnetic impurity with S=1 which is screened by the neighboring copper spins. In order to confirm the S=0 state of the Ni, we performed x-ray absorption spectroscopy (XAS) and compared the measurements to simulated XAS spectra based on multiplet ligand-field theory. Furthermore, Zn doping leads to much smaller effects on both the NMR spectra and the spin-lattice relaxation rates, indicating that Zn avoids occupying Cu sites. For magnetic Co impurities, T1-1 does not obey the gaplike decrease, and the low-temperature spectra get very broad. This could be related to an increase of the Néel temperature and is most likely an effect of the impurity spin S≠0.

Details

OriginalspracheEnglisch
Aufsatznummer115135
FachzeitschriftPhysical Review B
Jahrgang96
Ausgabenummer11
PublikationsstatusVeröffentlicht - 19 Sept. 2017
Peer-Review-StatusJa

Externe IDs

ORCID /0000-0002-2438-0672/work/158767757