A first-principles study of the structural phase transition in Ta<sub>2</sub>NiSe<sub>5</sub>

ORAL

Abstract

Ta2NiSe5, a quasi one-dimensional material, undergoes a structural phase transition from a high temperature orthorhombic phase to a low temperature monoclinic phase at around 330K, accompanied by a transition from metal to insulator. Previous studies suggest that the transition may be driven by formation of excitons and the low temperature phase of Ta2NiSe5 is a possible candidate for an excitonic insulator phase. We have performed density functional theory (DFT) calculations to investigate the structural and electronic properties of this system. Simulations of structural changes as a function of temperature and charge doping are consistent with the observed monoclinic-orthorhombic structural transition, and the corresponding electronic structure shows good agreement with recent angle-resolved photoemission spectroscopy (ARPES) data [1]. Further analysis of the electronic structure of the system will be presented.

*This work was supported by the Department of Energy within the Theory of Materials Program at the Lawrence Berkeley National Laboratory under under Contract No. DE-AC02-05-CH11231.

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Publication: [1] C. Chen, X. Chen, W. Tang, Z. Li, S. Wang, S. Ding, C. Jozwiak, A. Bostwick, E. Rotenberg, M. Hashimoto, D. Lu, J. Ruff, S. G. Louie, R. Birgeneau, Y. Chen, Y. Wang, Y. He, in preparation.

Presenters

  • Weichen Tang

    • University of California at Berkeley and Lawrence Berkeley National Laboratory
    • University of California, Berkeley

Authors

  • Weichen Tang

    • University of California at Berkeley and Lawrence Berkeley National Laboratory
    • University of California, Berkeley

  • Zhenglu Li

    • University of California at Berkeley, and Lawrence Berkeley National Laboratory
    • Physics Department, UC Berkeley and Lawrence Berkeley National Lab
    • Lawrence Berkeley National Laboratory
    • Lawrence Berkeley National Laboratory; University of California at Berkeley
    • University of California at Berkeley and Lawrence Berkeley National Laboratory

  • Steven G Louie

    • University of California at Berkeley, and Lawrence Berkeley National Laboratory
    • Physics Department, UC Berkeley and Lawrence Berkeley National Lab
    • University of California Berkeley
    • University of California, Berkeley
    • University of California at Berkeley; Lawrence Berkeley National Laboratory
    • University of California at Berkeley and Lawrence Berkeley National Laboratory
    • UC berkeley
    • University of California at Berkeley and Lawrence Berkeley National Lab
    • UC Berkeley & Lawrence Berkeley National Laboratory