Insulator-Metal Transition in Two-dimensional Mott Insulator NiPS<sub>3</sub> under pressure

ORAL

Abstract

NiPS3 crystallizes in a monoclinic C2/m structure at ambient pressure. The Ni ions form a honeycomb lattice, and each layer is isolated between two layers of S and P triangles (PS3), separated by van der Waals (vdW) gaps. Below 155 K, NiPS3 orders anti-ferromagnetically with the magnetic moment directed mostly along the c axis.1 There is a prediction that pressure-induced Mott insulator to metal transition (IMT) might be accompanied by the |SZ| = 1 to |SZ| = 1/2 state without changing crystal structure.2 The electronically-driven IMT suggests that NiPS3 is a promising material for ultrafast resistivity switching. We performed electrical resistance and XRD measurements under quasi-uniaxial pressure and observed a sluggish IMT at 35 GPa accompanied by a structure change. This work did not observe superconductivity down to 2 K in contrast to FePSe3 (max Tc ~ 5.5 K at 30 GPa)4. The observed structure evolution differs from earlier reports that applied a different pressure media.3 It is suggested that the phase stability fields of NiPS3 are highly dependent on the stress state.

[1] Wildes et al., Phys. Rev. B 92, 224408 (2015).

[2] H.S. Kim et al., Phys. Rev. Lett. 123, 236401 (2019).

[3] X. Ma et al., Sci. China Physics, Mech. Astron. 64, 297011 (2021).

[4] Y. Wang et al. Nature Communications 9, 1914 (2018)

*Gordon and Betty Moore Foundation's EPiQS Initiative, Grant GBMF9069 to David Mandrus. The U.S. DOE, Office of Science, Basic Energy Sciences, under Award No. DE-SC0020321 to Maik Lang. A portion of this research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the ORNL. XRD experiments were performed at HPCAT (Sector 16), APS, ANL. HPCAT operations are supported by DOE-NNSA's Office of Experimental Sciences. The APS is a U.S. DOE Office of Science User Facility operated for the DOE Office of Science by ANL under Contract No. DE-AC02-06CH11357. A part of HPCAT beam time was provided by the Chicago/DOE Alliance Center.

–

Publication: T. Matsuoka et al., 'Pressure-Induced Insulator-Metal Transition in Two-Dimensional Mott Insulator NiPS3' (Accepted to Journal of Physical Society of Japan)

Presenters

  • Takahiro Matsuoka

    • University of Tennessee

Authors

  • Takahiro Matsuoka

    • University of Tennessee

  • Rui Xue

    • University of Tennessee

  • Amanda V Haglund

    • University of Tennesseea
    • University of Tennessee
    • Department of Materials Science and Engineering, The University of Tennessee

  • Jesse S Smith

    • Argonne National Laboratory

  • Maik Lang

    • University of Tennessee

  • Antonio M dos Santos

    • Oak Ridge National Lab

  • David G Mandrus

    • University of Tennessee
    • Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN, 37916, USA