Characterization of the spin-1/2 linear-chain ferromagnet CuAs₂O₄

Autor(en)

Kevin Caslin, Reinhard Karl Kremer, Fereidoon S. Razavi, Armin Schulz, Alfonso Munoz, Franz Pertlik, Jihe Liu, Mike H. Whangbo, Joseph Law

Abstrakt

The magnetic and lattice properties of the S=1/2 quantum-spin-chain ferromagnet CuAs2O4, mineral name trippkeite, were investigated. The crystal structure of CuAs2O4 is characterized by the presence of corrugated CuO2 ribbon chains. Measurements of the magnetic susceptibility, heat capacity, electron paramagnetic resonance, and Raman spectroscopy were performed. Our experiments conclusively show that a ferromagnetic transition occurs at ∼7.4 K. Ab initio DFT calculations reveal dominant ferromagnetic nearest-neighbor and weaker antiferromagnetic next-nearest-neighbor spin exchange interactions along the ribbon chains. The ratio of Jnn/Jnnn is near −4, placing CuAs2O4 in close proximity to a quantum critical point in the Jnn-Jnnn phase diagram. TMRG simulations used to analyze the magnetic susceptibility confirm this ratio. Single-crystal magnetization measurements indicate that a magnetic anisotropy forces the Cu2+ spins to lie in an easy plane perpendicular to the c axis. An analysis of the field- and temperature-dependent magnetization by modified Arrott plots reveals a 3d-XY critical behavior. Lattice perturbations induced by quasihydrostatic pressure and temperature were mapped via magnetization and Raman spectroscopy.

Organisation(en)

Institut für Mineralogie und Kristallographie

Externe Organisation(en)

Brock University, Universidad de La Laguna, Max-Planck-Institut für Festkörperforschung, North Carolina State University, Helmholtz-Zentrum Dresden-Rossendorf

Journal

Physical Review B

Band

89

Anzahl der Seiten

11

ISSN

1098-0121

DOI

https://doi.org/10.1103/PhysRevB.89.014412

Publikationsdatum

01-2014

Peer-reviewed

Ja

ÖFOS 2012

104003 Anorganische Chemie, 105113 Kristallographie, 104006 Festkörperchemie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/e327ff94-0194-47dc-86c3-91babd84bfd6