Correlation Driven Magnetic Frustration and Insulating Behavior of TiF3

ORAL

Abstract

We investigate the halide perovskite TiF3, renowned for its intricate interplay between structure, electronic correlations, magnetism, and thermal expansion. Despite its simple structure, understanding its low-temperature magnetic behavior has been a challenge. Previous theories proposed antiferromagnetic ordering. In contrast, experimental signatures for an ordered magnetic state are absent down to 10~K. Our current study has successfully reevaluated the theoretical modeling of TiF$_3$, unveiling the significance of strong electronic correlations as the key driver for its insulating behavior and magnetic frustration. In addition, our frequency-dependent optical reflectivity measurements exhibit clear signs of an insulating state. Analysis of the calculated magnetic data gives an antiferromagnetic exchange coupling with a net Weiss temperature of order 25 K as well as a magnetic response consistent with a S=1/2 local moment per Ti3+. Yet, the system shows no susceptibility peak at this temperature scale and appears free of long-range antiferromagnetic order down to 1 K. Extending ab initio modeling of the material to larger unit cells shows a tendency for relaxing into a non-collinear magnetic ordering, with a shallow energy landscape between several magnetic ground states, promoting the status of this simple, nearly cubic perovskite structured material as a candidate spin liquid.

[1] Gayanath W. Fernando, Donal Sheets, Jason Hancock, Arthur Ernst, R. Matthias Geilhufe, Correlation Driven Magnetic Frustration and Insulating Behavior of TiF3, arXiv:2310.12645 (2023)

[2] D. Sheets, K. Lyszak, M. Jain, J. Hancock, G. W. Fernando, I. Sochnikov, J. Franklin, and R. M. Geilhufe, Spin-1/2 Mott state in negative thermal expansion perovskite TiF3, in preparation (2023)

* We acknowledge support from the Swedish Research Council (No. 2022-03350), Chalmers University of Technology, the U.S. National Science Foundation (No. NSF-DMR-1905862), Fonds zur Förderung der Wissenschaftlichen Forschung (FWF) (Grant No. I 5384). We also acknowledge the computing resources provided by the Center for Functional Nanomaterials at Brookhaven National Laboratory (No. DE-SC0012704) and the Swedish National Infrastructure for Computing (SNIC).

–

Publication: [1] Gayanath W. Fernando, Donal Sheets, Jason Hancock, Arthur Ernst, R. Matthias Geilhufe, Correlation Driven Magnetic Frustration and Insulating Behavior of TiF3, arXiv:2310.12645 (2023)
[2] D. Sheets, K. Lyszak, M. Jain, J. Hancock, G. W. Fernando, I. Sochnikov, J. Franklin, and R. M. Geilhufe, Spin-1/2 mott state in negative thermal expansion perovskite TiF3, submitted to PRB (2023)

Presenters

  • GAYANATH W FERNANDO

    University of Connecticut

Authors

  • R. Matthias Geilhufe

    Chalmers University, Chalmers Univ of Tech

  • GAYANATH W FERNANDO

    University of Connecticut

  • Donal Sheets

    University of Connecticut

  • Arthur Ernst

    Johannes Kepler University, Altenbergerstraβe 69, Linz 4040, Austria, Johannes Kepler University Linz, Max Planck Institute of Microstructure Physics

  • Jason N Hancock

    University of Connecticut