Probing the quantum phase transition in Mott insulator BaCoS2 tuned by pressure and Ni substitution

Z. Guguchia, B. A. Frandsen, D. Santos-Cottin, S. C. Cheung, Z. Gong, Q. Sheng, K. Yamakawa, A. M. Hallas, M. N. Wilson, Y. Cai, J. Beare, R. Khasanov, R. De Renzi, G. M. Luke, S. Shamoto, A. Gauzzi, Y. Klein, and Y. J. Uemura
Phys. Rev. Materials 3, 045001 – Published 5 April 2019

Abstract

We present a muon spin relaxation study of the Mott transition in BaCoS2 using two independent control parameters: (i) pressure p to tune the electronic bandwidth and (ii) Ni substitution x on the Co site to tune the band filling. For both tuning parameters, the antiferromagnetic insulating state first transitions to an antiferromagnetic metal and finally to a paramagnetic metal without undergoing any structural phase transition. BaCoS2 under pressure displays minimal change in the ordered magnetic moment Sord until it collapses abruptly upon entering the antiferromagnetic metallic state at pcr1.3GPa. In contrast, Sord in the Ni-doped system Ba(Co1xNix)S2 steadily decreases with increasing x until the antiferromagnetic metallic region is reached at xcr0.22. In both cases, significant phase separation between regions with static magnetic order and paramagnetic/nonmagnetic regions develops when approaching pcr or xcr, and the antiferromagnetic metallic state is characterized by weak, random, static magnetism in a small volume fraction. No dynamical critical behavior is observed near the transition for either tuning parameter. These results demonstrate that the quantum evolution of both the bandwidth- and filling-controlled metal-insulator transition at zero temperature proceeds as a first-order transition. This behavior is common to magnetic Mott transitions in RNiO3 and V2O3, which are accompanied by structural transitions without the formation of an antiferromagnetic metal phase.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Received 21 January 2019

DOI:https://doi.org/10.1103/PhysRevMaterials.3.045001

©2019 American Physical Society

Physics Subject Headings (PhySH)

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

Z. Guguchia1,2, B. A. Frandsen3, D. Santos-Cottin4, S. C. Cheung1, Z. Gong1, Q. Sheng1, K. Yamakawa1, A. M. Hallas5, M. N. Wilson5, Y. Cai5, J. Beare5, R. Khasanov2, R. De Renzi6, G. M. Luke5,7,8, S. Shamoto9, A. Gauzzi10, Y. Klein10, and Y. J. Uemura1,*

  • 1Department of Physics, Columbia University, New York, New York 10027, USA
  • 2Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
  • 3Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602, USA
  • 4LPEM – ESPCI Paris, PSL Research University, CNRS, 10 rue Vauquelin, F-75005 Paris, France
  • 5Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, Canada L8S 4M1
  • 6Department of Mathematical, Physical and Computer Sciences, Parco delle Scienze 7A, I-43124 Parma, Italy
  • 7Canadian Institute for Advanced Research, Toronto, Ontario, Canada M5G 1Z7
  • 8TRIUMF, Vancouver, British Columbia, Canada V6T 2A3
  • 9Advanced Science Research Center, Japan Atomic Energy Agency (JAEA), Tokai, Naka, Ibaraki 319-1195, Japan
  • 10Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), Sorbonne Université, CNRS, IRD, MNHN, 4 place Jussieu 75005 Paris, France

  • *yu2@columbia.edu

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 3, Iss. 4 — April 2019

Reuse & Permissions
Access Options
CHORUS

Article Available via CHORUS

Download Accepted Manuscript
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Materials

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×