Lattice dynamics and structural transition of the hyperhoneycomb iridate βLi2IrO3 investigated by high-pressure Raman scattering

Sungkyun Choi, Heung-Sik Kim, Hun-Ho Kim, Aleksandra Krajewska, Gideok Kim, Matteo Minola, Tomohiro Takayama, Hidenori Takagi, Kristjan Haule, David Vanderbilt, and Bernhard Keimer
Phys. Rev. B 101, 054102 – Published 7 February 2020
PDFHTMLExport Citation

Abstract

We report a polarized Raman scattering study of the lattice dynamics of βLi2IrO3 under hydrostatic pressures up to 7.62 GPa. At ambient pressure, βLi2IrO3 exhibits the hyperhoneycomb crystal structure and a magnetically ordered state of spin-orbit entangled Jeff = 1/2 moments that are strongly influenced by bond-directional (Kitaev) exchange interactions. At a critical pressure of 4.1 GPa, the phonon spectrum changes abruptly, consistent with the reported structural transition into a monoclinic, dimerized phase. A comparison to the phonon spectra obtained from density-functional calculations shows reasonable overall agreement. The calculations also indicate that the high-pressure phase is a nonmagnetic insulator driven by the formation of Ir–Ir dimer bonds. Our results thus indicate a strong sensitivity of the electronic properties of βLi2IrO3 to the pressure-induced structural transition.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Received 28 July 2019
  • Revised 8 October 2019
  • Accepted 23 December 2019

DOI:https://doi.org/10.1103/PhysRevB.101.054102

©2020 American Physical Society

Physics Subject Headings (PhySH)

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

Sungkyun Choi1,*, Heung-Sik Kim2,3, Hun-Ho Kim1, Aleksandra Krajewska1, Gideok Kim1, Matteo Minola1, Tomohiro Takayama1, Hidenori Takagi1, Kristjan Haule2, David Vanderbilt2, and Bernhard Keimer1

  • 1Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany
  • 2Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
  • 3Department of Physics, Kangwon National University, 1 Gangwondaehak-gil, Chuncheon-si, Gangwon-do 24341, Republic of Korea

  • *Present address: Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA; sc1853@physics.rutgers.edu

Article Text (Subscription Required)

Click to Expand

Supplemental Material (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 101, Iss. 5 — 1 February 2020

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 B

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×